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Money & sharing3 tools⌄
Tip calculator
Calculate a tip, total and per-person amount without sending your bill anywhere.
Open tool Browser-onlyEqual split
Split a bill evenly, including an optional tip, tax and service charge.
Open tool Browser-onlyWeighted split
Divide a total fairly when people should pay different shares.
Open toolDate & age4 tools⌄
Age calculator
Calculate exact age in years, months and days, total days lived and the next birthday.
Open tool Browser-onlyDate difference
Find the elapsed years, months, days, weeks and total days between two dates.
Open tool Browser-onlyDays until
Count calendar days and weeks until a future date or since a past date.
Open tool Browser-onlyBusiness days
Count weekdays between two dates with optional excluded holiday dates.
Open toolGrades3 tools⌄
Grade calculator
Convert points earned and points possible into a percentage and letter grade.
Open tool Browser-onlyFinal grade
Calculate the score needed on a final exam to reach a target course grade.
Open tool Browser-onlyWeighted grade
Combine assignment or category grades using percentage weights.
Open toolRandom & decisions5 tools⌄
Random number
Generate one or more cryptographically random integers inside a selected range.
Open tool Browser-onlyCoin flip
Flip an animated virtual coin and get a fair heads-or-tails result instantly.
Open tool Browser-onlyPicker wheel
Paste choices, spin an animated wheel and select one locally at random.
Open tool Browser-onlyName spinner
Paste names, spin an animated wheel and choose a winner fairly in your browser.
Open tool Browser-onlyTeam generator
Shuffle a list of people into balanced random teams.
Open toolQR codes2 tools⌄
Percentages14 tools⌄
Percentage calculator
Solve common percentage questions with clear inputs and instant local results.
Open tool Browser-onlyReverse percentage
Recover an original value from a known result after a percentage increase or decrease.
Open tool Browser-onlyStandard calculator
Use a fast keyboard-friendly calculator for arithmetic, percentages, powers and common scientific functions.
Open tool Browser-onlyFunction plotter
Plot up to three mathematical functions with adjustable axes, zoom controls and accessible sample values.
Open tool Browser-onlyTemperature converter
Convert Celsius, Fahrenheit and Kelvin instantly in either direction.
Open tool Browser-onlyDistance converter
Convert kilometres, miles, metres, feet, inches, yards and nautical miles.
Open tool Browser-onlyWeight converter
Convert kilograms, pounds, ounces, stone, grams and milligrams.
Open tool Browser-onlyVolume converter
Convert litres, millilitres, US and imperial gallons, cups and fluid ounces.
Open tool Browser-onlyArea converter
Convert square metres, square feet, acres, hectares and square kilometres.
Open tool Browser-onlySpeed converter
Convert kilometres per hour, miles per hour, metres per second and knots.
Open tool Browser-onlyFuel economy converter
Convert L/100 km, US MPG, imperial MPG and kilometres per litre.
Open tool Browser-onlyPressure converter
Convert bar, PSI, pascals, kilopascals, atmospheres and millimetres of mercury.
Open tool Browser-onlyData storage converter
Convert bytes, bits, decimal KB/MB/GB/TB and binary KiB/MiB/GiB/TiB.
Open tool Browser-onlyTime converter
Convert milliseconds, seconds, minutes, hours, days, weeks and common year lengths.
Open toolWords & word games6 tools⌄
Anagram solver
Find English words that use every scrambled letter exactly once, including optional blanks.
Open tool Browser-onlyWord unscrambler
Unscramble letters into English words of different lengths without uploading your letter rack.
Open tool Browser-onlyWordfeud solver
Find playable-looking English words from rack letters and rank them by estimated Wordfeud base score.
Open tool Browser-onlyScrabble word finder
Build English words from rack letters and sort them by estimated Scrabble base tile score.
Open tool Browser-onlyWords With Friends solver
Find English rack words and rank them with estimated Words With Friends base letter values.
Open tool Browser-onlyCrossword solver
Find English words matching known letters and question-mark blanks in a crossword pattern.
Open toolEconomics182 tools⌄
Inflation
Estimate how inflation changes the future price of an amount over time.
Open tool Browser-onlyPurchasing power
Estimate what today's money may buy after inflation reduces its purchasing power.
Open tool Browser-onlySalary vs inflation
Compare a salary change with inflation to see whether real pay rose or fell.
Open tool Browser-onlyRequired salary
Calculate the future salary needed to preserve today's purchasing power.
Open tool Browser-onlyReal interest rate
Compare nominal interest with inflation using approximate and exact Fisher calculations.
Open tool Browser-onlyReal investment return
Adjust a nominal investment return for inflation and estimate real ending value.
Open tool Browser-onlyBreak-even
Find the unit sales needed to cover fixed and variable costs.
Open tool Browser-onlyMargin
Calculate gross profit and margin from revenue and cost.
Open tool Browser-onlyMarkup
Calculate markup from unit cost and selling price.
Open tool Browser-onlyContribution margin
Measure how much sales revenue remains after variable costs.
Open tool Browser-onlyPrice elasticity
Calculate arc price elasticity and classify demand as elastic or inelastic.
Open tool Browser-onlyPrice change revenue
Estimate how a price change could affect quantity demanded and revenue using an elasticity assumption.
Open tool Browser-onlyConsumer surplus
Calculate consumer surplus for a linear demand curve.
Open tool Browser-onlyMarket equilibrium
Solve equilibrium price and quantity for linear supply and demand equations.
Open tool Browser-onlyTax incidence
Estimate how a per-unit tax is divided between consumers and producers using elasticities.
Open tool Browser-onlySupply elasticity
Calculate midpoint price elasticity of supply and classify producer responsiveness.
Open tool Browser-onlyIncome elasticity
Measure how demand changes with income and classify the type of good.
Open tool Browser-onlyCross-price elasticity
Estimate whether two goods behave like substitutes or complements.
Open tool Browser-onlyProducer surplus
Calculate producer surplus for a linear supply curve.
Open tool Browser-onlyTotal surplus
Calculate combined consumer and producer surplus in a linear market.
Open tool Browser-onlyTax deadweight loss
Estimate tax revenue and deadweight loss from a reduction in traded quantity.
Open tool Browser-onlyPrice ceiling shortage
Calculate quantity demanded, quantity supplied and shortage under a price ceiling.
Open tool Browser-onlyPrice floor surplus
Calculate quantity demanded, quantity supplied and surplus under a price floor.
Open tool Browser-onlyTarget profit quantity
Find the unit sales required to cover costs and reach a chosen operating-profit target.
Open tool Browser-onlyCost-plus pricing
Turn a unit cost and desired markup into a selling price, profit per unit and gross margin.
Open tool Browser-onlyMonopoly analysis
Solve the profit-maximising price, output and profit for linear demand and constant marginal cost.
Open tool Browser-onlyMarginal revenue
Estimate marginal revenue from the change in total revenue across two output levels.
Open tool Browser-onlyMarginal cost
Estimate marginal cost from a change in total cost and output.
Open tool Browser-onlyHHI market concentration
Calculate HHI by summing the squared market shares of up to five firms.
Open tool Browser-onlyFour-firm concentration
Measure the combined market share controlled by the four largest firms.
Open tool Browser-onlyCobb-Douglas production
Estimate output, labour productivity and returns to scale from a Cobb-Douglas production function.
Open tool Browser-onlyBudget line
Calculate budget intercepts and the affordable amount of one good after choosing another.
Open tool Browser-onlyLabour efficiency
Measure output per labour hour, compensation per output unit and compensation per hour.
Open tool Browser-onlyLinear demand equation
Derive a linear demand equation from two observed price-and-quantity points and predict demand at another price.
Open tool Browser-onlyLinear supply equation
Derive a linear supply equation from two observed price-and-quantity points and predict supply at another price.
Open tool Browser-onlyDemand shift impact
See how a parallel shift in linear demand changes market equilibrium price and quantity.
Open tool Browser-onlySupply shift impact
See how a parallel shift in linear supply changes market equilibrium price and quantity.
Open tool Browser-onlyPoint demand elasticity
Calculate price elasticity at a specific point on a linear demand curve.
Open tool Browser-onlyTarget quantity price
Find the price associated with a target quantity on a linear demand curve.
Open tool Browser-onlyAverage and marginal product
Calculate average product of labour and marginal product between two production observations.
Open tool Browser-onlyCost curves
Calculate total, average fixed, average variable, average total and marginal cost from two output observations.
Open tool Browser-onlyEconomic profit
Compare accounting profit with economic profit after including implicit opportunity costs.
Open tool Browser-onlyShutdown point
Compare price with average variable cost and estimate the short-run operating result.
Open tool Browser-onlyMarginal utility
Estimate the additional utility gained per extra unit consumed between two observations.
Open tool Browser-onlyUtility per dollar
Compare the marginal utility received per currency unit from two goods.
Open tool Browser-onlyUtility-maximising bundle
Find the Cobb-Douglas consumer bundle that allocates a budget between two goods.
Open tool Browser-onlyIncome and substitution effects
Decompose a quantity change into substitution and income effects using a compensated quantity.
Open tool Browser-onlyIsoquant input requirement
Find the capital input required to reach a target output with a chosen labour input.
Open tool Browser-onlyIsocost input combination
Find the capital affordable after choosing labour under a fixed production budget.
Open tool Browser-onlyCost-minimising inputs
Find the cost-minimising labour and capital mix for a Cobb-Douglas production target.
Open tool Browser-onlyDiminishing returns
Compare marginal product across two successive labour intervals to detect diminishing returns.
Open tool Browser-onlyOpportunity cost
Compare the value of a chosen option with the best alternative forgone.
Open tool Browser-onlySunk cost decision
Evaluate a forward-looking decision using future benefits and avoidable future costs while separating sunk cost.
Open tool Browser-onlyEconomies of scale
Compare average cost at two output levels and measure whether unit cost falls as production expands.
Open tool Browser-onlyTotal and average revenue
Calculate total revenue and average revenue from price and quantity sold.
Open tool Browser-onlyPer-unit tax equilibrium
Solve post-tax consumer price, producer price, quantity, tax revenue and deadweight loss for linear supply and demand.
Open tool Browser-onlySubsidy equilibrium
Solve consumer price, producer receipt, quantity and government cost after a per-unit subsidy.
Open tool Browser-onlyExternality correction
Estimate a Pigouvian tax or subsidy from marginal external cost or benefit.
Open tool Browser-onlyCompetitive firm output
Find a competitive firm's profit-maximising output where market price equals linear marginal cost.
Open tool Browser-onlyLerner index
Measure price-cost markup and implied market power using price and marginal cost.
Open tool Browser-onlyCournot duopoly
Solve quantities, market price and operating profits for two Cournot competitors with linear demand and constant marginal costs.
Open tool Browser-onlyDiscount profitability
Estimate how a price discount and expected volume response change gross profit.
Open tool Browser-onlyMarginal revenue product
Calculate the additional revenue generated by one more unit of labour.
Open tool Browser-onlyGDP growth
Calculate the percentage change in GDP between two periods.
Open tool Browser-onlyGDP deflator
Calculate the GDP price deflator from nominal and real GDP.
Open tool Browser-onlyFiscal multiplier
Explore the textbook government-spending multiplier from the marginal propensity to consume.
Open tool Browser-onlyGDP CAGR
Calculate the annualised compound growth rate between two GDP values.
Open tool Browser-onlyNominal vs real GDP
Convert nominal GDP into real GDP using a GDP deflator.
Open tool Browser-onlyGDP per capita
Divide total GDP by population to estimate output per person.
Open tool Browser-onlyGDP per capita growth
Calculate the change in GDP per person between two periods.
Open tool Browser-onlyOutput gap
Compare actual GDP with estimated potential GDP.
Open tool Browser-onlyRule of 70
Estimate how long a growing economic value takes to double.
Open tool Browser-onlyCPI
Calculate a price index from current and base-period basket costs.
Open tool Browser-onlyInflation from CPI
Calculate inflation between two consumer price index readings.
Open tool Browser-onlyUnemployment rate
Calculate unemployment as a share of the labour force.
Open tool Browser-onlyLabour participation
Calculate the share of the working-age population participating in the labour force.
Open tool Browser-onlyArc elasticity
Measure elasticity between two points using the midpoint method.
Open tool Browser-onlyElasticity classifier
Classify a supplied elasticity as elastic, inelastic or unit elastic.
Open tool Browser-onlyShortage or surplus
Compare quantity demanded with quantity supplied at a selected price.
Open tool Browser-onlyTax revenue
Calculate government revenue from a per-unit tax and post-tax sales quantity.
Open tool Browser-onlyCost components
Combine fixed and variable costs and calculate cost per unit.
Open tool Browser-onlyProfit-maximising output
Solve the output where a linear marginal-revenue curve equals constant marginal cost.
Open tool Browser-onlyMarket share
Calculate a firm's sales as a percentage of total market sales.
Open tool Browser-onlyCapacity utilisation
Compare actual output with maximum practical productive capacity.
Open tool Browser-onlyOperating leverage
Estimate how strongly operating profit responds to a change in sales.
Open tool Browser-onlyUnit economics
Calculate contribution, contribution margin and break-even volume per unit sold.
Open tool Browser-onlyEmployment rate
Calculate employed people as a share of the labour force.
Open tool Browser-onlyEmployment-to-population
Measure employed people as a share of the working-age population.
Open tool Browser-onlyUnemployment gap
Compare the actual unemployment rate with an estimated natural rate.
Open tool Browser-onlyMisery index
Add inflation and unemployment rates into the traditional misery index.
Open tool Browser-onlyTax multiplier
Calculate the simple Keynesian tax multiplier and predicted GDP effect.
Open tool Browser-onlyBalanced-budget multiplier
Combine equal government-spending and tax changes in the simple multiplier model.
Open tool Browser-onlyMPC
Calculate how much of an income change is spent on consumption.
Open tool Browser-onlyMPS
Calculate how much of an income change is saved.
Open tool Browser-onlyDisposable income
Calculate income after direct taxes plus transfers received.
Open tool Browser-onlyGovernment deficit
Calculate the difference between total government spending and revenue.
Open tool Browser-onlyPrimary balance
Calculate the budget balance before interest payments on public debt.
Open tool Browser-onlyDebt-to-GDP
Express public debt as a percentage of annual GDP.
Open tool Browser-onlyDeficit-to-GDP
Express a government deficit as a percentage of GDP.
Open tool Browser-onlyDebt dynamics
Estimate next-period debt-to-GDP from interest, growth and the primary balance.
Open tool Browser-onlyMoney multiplier
Calculate the simple deposit multiplier from a reserve ratio.
Open tool Browser-onlyRequired reserves
Calculate required and excess reserves from deposits and a reserve ratio.
Open tool Browser-onlyDeposit expansion
Estimate maximum textbook deposit expansion from an initial reserve injection.
Open tool Browser-onlyQuantity theory of money
Use MV = PY to connect money, velocity, prices and real output.
Open tool Browser-onlyReal money supply
Deflate nominal money balances by a price-level index.
Open tool Browser-onlyMonetary growth
Estimate money growth consistent with inflation, output growth and velocity growth.
Open tool Browser-onlyCurrency appreciation
Calculate appreciation when a currency buys more foreign currency than before.
Open tool Browser-onlyCurrency depreciation
Calculate depreciation when a currency buys less foreign currency than before.
Open tool Browser-onlyInterest-rate spread
Calculate the difference between two interest rates in percentage points and basis points.
Open tool Browser-onlyMarket-share growth
Measure percentage-point and relative growth in market share.
Open tool Browser-onlyMarkup from elasticity
Estimate a profit-maximising price from marginal cost and demand elasticity.
Open tool Browser-onlyBertrand competition
Explore the homogeneous-product Bertrand price outcome from two marginal costs.
Open tool Browser-onlyPrice discrimination
Compare profit from two customer segments charged different prices.
Open tool Browser-onlyMinimum viable price
Calculate the unit price required to cover costs and a target profit at a planned volume.
Open tool Browser-onlyCAC break-even
Calculate how many contribution periods are needed to recover customer acquisition cost.
Open tool Browser-onlyInventory turnover
Calculate how often average inventory is sold or used during a period.
Open tool Browser-onlyTariff welfare
Estimate tariff revenue and simple deadweight loss from reduced imports.
Open tool Browser-onlyPigouvian tax
Calculate the corrective tax and revenue implied by marginal external damage.
Open tool Browser-onlyFuture consumption
Calculate future consumption available by saving present income at a real return.
Open tool Browser-onlyLabour demand
Compare marginal revenue product with the wage cost of an additional worker or hour.
Open tool Browser-onlyWage equilibrium
Solve equilibrium wage and employment from linear labour demand and supply.
Open tool Browser-onlyMinimum-wage impact
Estimate labour demanded, labour supplied and excess supply at a selected wage floor.
Open tool Browser-onlyEmployment elasticity
Measure employment responsiveness to a change in output using midpoint percentages.
Open tool Browser-onlyCapital productivity
Calculate output produced per unit of capital input.
Open tool Browser-onlyEconomic rent
Calculate earnings above the minimum required to keep a factor in its current use.
Open tool Browser-onlyFactor-income distribution
Calculate labour, land, capital and profit shares of total factor income.
Open tool Browser-onlyPrice-volume-profit
Calculate profit and break-even volume from price, volume and cost assumptions.
Open tool Browser-onlyBundle pricing
Compare a bundle price with separate-item prices and calculate bundle contribution.
Open tool Browser-onlyTwo-part tariff
Calculate customer payment and seller contribution from an access fee plus per-unit charge.
Open tool Browser-onlyAffordable bundle
Check whether a two-good bundle is affordable and calculate the remaining budget.
Open tool Browser-onlyRevealed preference
Compare the cost of a chosen bundle with an alternative at the same observed prices.
Open tool Browser-onlyAd valorem tax
Calculate a percentage-based commodity tax, tax-inclusive price and total revenue.
Open tool Browser-onlyPrice-control welfare loss
Estimate traded quantity and deadweight loss under a binding price ceiling or floor.
Open tool Browser-onlyUnit labour cost
Calculate labour compensation paid per unit of real output.
Open tool Browser-onlyValue-based pricing
Estimate a price by capturing a selected share of measurable customer value.
Open tool Browser-onlyGDP expenditure approach
Calculate gross domestic product from consumption, investment, government spending and net exports.
Open tool Browser-onlyTrade balance
Calculate the trade balance and classify it as a surplus, deficit or balance.
Open tool Browser-onlyTerms of trade
Calculate the ratio of export prices to import prices as an index.
Open tool Browser-onlyPPP exchange rate
Estimate an implied exchange rate from the price of the same basket in two currencies.
Open tool Browser-onlyNominal GDP
Convert real GDP into nominal GDP using a GDP deflator.
Open tool Browser-onlyGDP income approach
Estimate GDP by adding factor incomes and net taxes on production.
Open tool Browser-onlyNational saving
Calculate national saving as income not used for consumption or government purchases.
Open tool Browser-onlyCurrent account
Calculate the current account from trade, net primary income and net transfers.
Open tool Browser-onlyMarginal propensity to import
Measure how much imports change when national income changes.
Open tool Browser-onlyOpen-economy multiplier
Estimate the spending multiplier when taxes and imports create additional leakages.
Open tool Browser-onlyOkun's law
Estimate an unemployment-rate change from actual and potential output growth.
Open tool Browser-onlyPhillips curve
Estimate inflation from expected inflation and the unemployment gap.
Open tool Browser-onlyLabour productivity growth
Calculate output per labour unit and its growth between two periods.
Open tool Browser-onlyReal wage growth
Adjust nominal wage growth for inflation to measure purchasing-power growth.
Open tool Browser-onlyReal exchange rate
Adjust a nominal exchange rate for relative domestic and foreign price levels.
Open tool Browser-onlyCash runway
Estimate how many months a business can operate at its current net cash burn.
Open tool Browser-onlyMonthly burn rate
Measure average monthly net cash burn from two cash balances.
Open tool Browser-onlyCurrent and quick ratios
Compare short-term assets with liabilities, with and without inventory.
Open tool Browser-onlyDebt service coverage
Compare operating cash available with required principal and interest payments.
Open tool Browser-onlyCustomer acquisition cost
Calculate acquisition cost per new customer from sales and marketing spending.
Open tool Browser-onlyMeeting cost
Estimate the labour cost of a meeting from attendance, time and loaded hourly cost.
Open tool Browser-onlyWorking capital requirement
Estimate operating cash tied up by inventory, receivables and supplier-payment timing.
Open tool Browser-onlyCash conversion cycle
Measure the days between paying for operations and collecting customer cash.
Open tool Browser-onlyLate-payment cost
Estimate the financing cost of an invoice remaining unpaid beyond its due date.
Open tool Browser-onlyEmergency cash reserve
Set a reserve target from essential monthly cash costs and desired coverage.
Open tool Browser-onlyGross burn rate
Calculate average monthly cash operating expenditure before revenue offsets.
Open tool Browser-onlySales commission
Calculate commission and total compensation from eligible sales and a commission rate.
Open tool Browser-onlyCustomer lifetime value
Estimate gross-profit lifetime value and value after acquisition cost.
Open tool Browser-onlyCAC payback period
Estimate how many months of gross profit recover customer acquisition cost.
Open tool Browser-onlySales conversion rate
Measure the percentage of leads or opportunities that became customers.
Open tool Browser-onlyRequired leads
Estimate the leads needed to reach a customer target at a chosen conversion rate.
Open tool Browser-onlyCustomer concentration
Summarise revenue concentration across the five largest customers.
Open tool Browser-onlyMRR and ARR
Convert monthly recurring revenue into annual recurring revenue.
Open tool Browser-onlyRevenue churn
Measure recurring revenue lost during a period as a share of starting revenue.
Open tool Browser-onlyCustomer churn
Measure customers lost during a period as a share of starting customers.
Open tool Browser-onlyNet revenue retention
Measure recurring revenue retained after churn, contraction and expansion.
Open tool Browser-onlyExpansion revenue
Measure added recurring revenue from existing customers.
Open tool Browser-onlySaaS gross margin
Calculate subscription gross profit and margin after service-delivery costs.
Open tool Browser-onlyBreak-even subscribers
Calculate subscribers needed to cover fixed costs at the selected unit economics.
Open tool Browser-onlyRequired subscription price
Find the price per subscriber needed for a target monthly profit.
Open tool Browser-onlyMonthly vs annual plan
Compare annual billing with twelve monthly payments and an annual discount.
Open tool Browser-onlyTrue employee cost
Estimate annual employment cost beyond base salary.
Open tool Browser-onlySalary to hourly cost
Convert annual loaded employment cost into cost per scheduled work hour.
Open tool Browser-onlyContractor vs employee
Compare annual contractor fees with loaded annual employee cost.
Open tool Browser-onlyOvertime cost
Calculate overtime pay from hours, base hourly rate and overtime multiplier.
Open tool Browser-onlyBillable utilisation
Measure billable hours as a percentage of available working hours.
Open tool Browser-onlyRequired billable rate
Find the hourly client rate needed to cover annual cost at target utilisation and margin.
Open toolMathematics170 tools⌄
Linear equation
Solve a linear equation in the form ax + b = c and see the isolation steps.
Open tool Browser-onlySlope
Calculate the slope of the line through two coordinate points.
Open tool Browser-onlyMidpoint
Find the point exactly halfway between two coordinates.
Open tool Browser-onlyDistance between points
Calculate straight-line distance between two coordinates.
Open tool Browser-onlyQuadratic formula
Solve ax² + bx + c = 0 and inspect the discriminant.
Open tool Browser-onlyTwo-equation system
Solve two linear equations in x and y using determinants.
Open tool Browser-onlyExponent
Raise a base to a selected power and see the repeated-multiplication meaning.
Open tool Browser-onlyLogarithm
Calculate a logarithm with any valid positive base.
Open tool Browser-onlyFraction simplifier
Reduce a fraction to lowest terms using the greatest common divisor.
Open tool Browser-onlyCircle
Calculate a circle's diameter, circumference and area from its radius.
Open tool Browser-onlyRectangle
Calculate area, perimeter and diagonal from length and width.
Open tool Browser-onlyTriangle area
Calculate triangle area from a base and perpendicular height.
Open tool Browser-onlyPythagorean theorem
Find the hypotenuse of a right triangle from its two legs.
Open tool Browser-onlyCylinder
Calculate cylinder volume and surface area from radius and height.
Open tool Browser-onlySphere
Calculate sphere volume and surface area from radius.
Open tool Browser-onlyRight triangle
Solve a right triangle from its two perpendicular legs.
Open tool Browser-onlyMean and median
Calculate the arithmetic mean and median of six values.
Open tool Browser-onlyStandard deviation
Calculate population and sample standard deviation for six values.
Open tool Browser-onlyProbability
Calculate event probability from favourable and total equally likely outcomes.
Open tool Browser-onlyCombinations and permutations
Count selections when order either matters or does not matter.
Open tool Browser-onlyPower-rule derivative
Differentiate a monomial axⁿ and evaluate its derivative at a selected x-value.
Open tool Browser-onlyPercentage change
Calculate the percentage increase or decrease between an original and a new value.
Open tool Browser-onlyRatio simplifier
Simplify a two-number whole-number ratio and calculate its decimal relationship.
Open tool Browser-onlyCone volume
Calculate the volume and base area of a circular cone from radius and height.
Open tool Browser-onlyTrapezoid area
Find trapezoid area from the two parallel base lengths and perpendicular height.
Open tool Browser-onlyDegrees and radians
Convert an angle entered in degrees to radians and common turn measures.
Open tool Browser-onlyPercentage of a number
Find a selected percentage of any number and see the decimal conversion.
Open tool Browser-onlyProportion solver
Solve a proportional relationship a/b = c/x by cross multiplication.
Open tool Browser-onlySquare root
Find the principal square root and verify it by squaring the result.
Open tool Browser-onlyRectangular prism
Calculate volume, surface area and space diagonal from length, width and height.
Open tool Browser-onlyCube dimensions
Calculate a cube's volume, surface area and space diagonal from its side length.
Open tool Browser-onlyData range
Find the minimum, maximum and range of six entered observations.
Open tool Browser-onlyZ-score
Standardise a value by measuring how many standard deviations it lies from the mean.
Open tool Browser-onlyPower-rule integral
Integrate a monomial axⁿ and evaluate its antiderivative at a selected x-value.
Open tool Browser-onlyGCF and LCM
Find the greatest common factor and least common multiple of two whole numbers.
Open tool Browser-onlyAbsolute value
Find a number's distance from zero and compare its original sign.
Open tool Browser-onlyCube root
Find the real cube root of a positive or negative number and verify it.
Open tool Browser-onlyEllipse
Calculate ellipse area and an accurate perimeter approximation from its semi-axes.
Open tool Browser-onlySquare pyramid
Calculate volume, slant height and total surface area from base side and vertical height.
Open tool Browser-onlyWeighted mean
Calculate the weighted mean of three values when observations have different importance or frequency.
Open tool Browser-onlyOdds to probability
Convert odds in favour into probability, percentage probability and odds against.
Open tool Browser-onlyDefinite power integral
Evaluate the definite integral of axⁿ between lower and upper bounds.
Open tool Browser-onlyLinear function
Evaluate f(x) = mx + b and identify its slope and vertical intercept.
Open tool Browser-onlyQuadratic function
Evaluate ax² + bx + c and calculate the parabola's vertex coordinates.
Open tool Browser-onlyArithmetic sequence
Find the nth term of a sequence with a constant difference.
Open tool Browser-onlyArithmetic series
Calculate the sum of the first n terms of an arithmetic sequence.
Open tool Browser-onlyGeometric sequence
Find the nth term of a sequence with a constant multiplication ratio.
Open tool Browser-onlyGeometric series
Calculate the sum of the first n terms of a finite geometric sequence.
Open tool Browser-onlyExponential function
Evaluate exponential growth or decay in the form f(x)=abˣ.
Open tool Browser-onlySine, cosine and tangent
Calculate sine, cosine and tangent for an angle entered in degrees.
Open tool Browser-onlyVector magnitude
Calculate the length of a three-dimensional vector from its components.
Open tool Browser-onlyVector addition
Add two three-dimensional vectors component by component.
Open tool Browser-onlyDot product
Calculate the scalar dot product of two three-dimensional vectors.
Open tool Browser-onlyCross product
Calculate the three-dimensional vector perpendicular to two input vectors.
Open tool Browser-onlyAngle between vectors
Find the angle between two three-dimensional vectors using their dot product.
Open tool Browser-only2×2 determinant
Calculate the determinant of a 2×2 matrix and identify whether it is invertible.
Open tool Browser-only2×2 matrix inverse
Invert a nonsingular 2×2 matrix and display all four inverse entries.
Open tool Browser-only2×2 eigenvalues
Calculate the real eigenvalues of a 2×2 matrix from its trace and determinant.
Open tool Browser-onlyExponential growth ODE
Solve y′=ky from an initial value and evaluate the solution at time t.
Open tool Browser-onlyHalf-life decay
Model exponential decay from an initial amount, half-life and elapsed time.
Open tool Browser-onlyLogistic growth ODE
Evaluate population growth with a carrying capacity using the logistic differential equation.
Open tool Browser-onlyNewton cooling
Estimate an object's temperature as it approaches a constant ambient temperature.
Open tool Browser-onlyFirst-order linear ODE
Solve y′+py=q with constant coefficients and an initial value.
Open tool Browser-onlyEuler method step
Approximate one step for y′=ay+b using the slope at the current point.
Open tool Browser-onlyHarmonic oscillator
Evaluate displacement and velocity for x″+ω²x=0 with amplitude and phase.
Open tool Browser-onlyDamped oscillator
Evaluate an underdamped oscillation x(t)=Ae⁻ᵝᵗcos(ωt+φ) and its decaying envelope.
Open tool Browser-onlyComplex addition
Add two complex numbers by combining their real and imaginary components.
Open tool Browser-onlyComplex multiplication
Multiply two complex numbers and display the rectangular-form result.
Open tool Browser-onlyComplex division
Divide one complex number by another using the denominator's conjugate.
Open tool Browser-onlyComplex polar form
Convert z=a+bi into magnitude and phase angle.
Open tool Browser-onlyEuler formula
Evaluate eⁱᶿ as cosine and sine components on the unit circle.
Open tool Browser-onlyPrincipal complex root
Calculate the principal nth root of a complex number in polar form.
Open tool Browser-onlyPhasor addition
Add two magnitude-phase phasors and return the combined magnitude and phase.
Open tool Browser-onlyFour-sample DFT
Calculate one discrete Fourier transform bin from four real-valued samples.
Open tool Browser-onlyConstant acceleration
Calculate final velocity and displacement under constant acceleration.
Open tool Browser-onlyProjectile motion
Calculate ideal launch components, flight time, maximum height and horizontal range.
Open tool Browser-onlyKinetic energy and momentum
Calculate classical linear momentum and kinetic energy from mass and velocity.
Open tool Browser-onlyWork and force angle
Calculate mechanical work done by a constant force over a displacement.
Open tool Browser-onlyNewton's second law
Calculate net force and weight from mass, acceleration and gravitational field strength.
Open tool Browser-onlyGravitational force
Calculate Newtonian gravitational attraction between two point masses.
Open tool Browser-onlyCoulomb force
Calculate the signed electrostatic force magnitude between two point charges.
Open tool Browser-onlyWave speed and wavelength
Calculate wave speed and period from frequency and wavelength.
Open tool Browser-onlyPhoton energy
Convert a photon wavelength into frequency, energy in joules and energy in electronvolts.
Open tool Browser-onlyDe Broglie wavelength
Calculate the matter wavelength associated with a non-relativistic particle's momentum.
Open tool Browser-onlyUncertainty principle
Calculate the minimum momentum and velocity uncertainty implied by a position uncertainty.
Open tool Browser-onlyWavefunction probability
Convert a complex wavefunction amplitude into magnitude, phase and probability density.
Open tool Browser-onlyTwo-state normalization
Normalize two real state amplitudes and calculate their measurement probabilities.
Open tool Browser-onlyBloch sphere state
Convert Bloch-sphere angles into qubit amplitudes and measurement probabilities.
Open tool Browser-onlyInfinite well energy
Calculate a particle's quantized energy level in a one-dimensional infinite square well.
Open tool Browser-onlyHydrogen transition
Calculate hydrogen energy levels and the photon energy and wavelength between two principal quantum numbers.
Open tool Browser-onlyFactorial
Calculate n factorial and see its multiplicative expansion.
Open tool Browser-onlyFibonacci number
Calculate the nth Fibonacci number by recurrence.
Open tool Browser-onlyTriangular number
Calculate the number of objects in a triangular arrangement.
Open tool Browser-onlySum 1 to n
Add every whole number from one through n.
Open tool Browser-onlyModulo
Find quotient and Euclidean remainder after integer division.
Open tool Browser-onlyPercentage difference
Compare two values symmetrically using their average magnitude.
Open tool Browser-onlyNth root
Calculate the real nth root of a number.
Open tool Browser-onlyChange-of-base logarithm
Evaluate a logarithm using natural logarithms.
Open tool Browser-onlyDistance, rate and time
Calculate distance from constant speed and elapsed time.
Open tool Browser-onlyRatio allocation
Split a total according to three ratio weights.
Open tool Browser-onlyAnnulus area
Calculate the area between two concentric circles.
Open tool Browser-onlySector area
Calculate the area enclosed by a central angle.
Open tool Browser-onlyArc length
Calculate circle arc length from radius and central angle.
Open tool Browser-onlyHeron's triangle area
Calculate triangle area from all three side lengths.
Open tool Browser-onlyParallelogram area
Calculate parallelogram area and perimeter.
Open tool Browser-onlyRhombus area
Calculate rhombus area from its diagonals.
Open tool Browser-onlyRegular polygon
Calculate regular polygon area and perimeter from side count and side length.
Open tool Browser-onlyPolygon interior angles
Calculate the interior-angle sum and regular interior angle.
Open tool Browser-only3D distance
Calculate Euclidean distance between two points in three dimensions.
Open tool Browser-onlyTorus geometry
Calculate the volume and surface area of a circular torus.
Open tool Browser-onlyCosine law side
Find a triangle side from two sides and their included angle.
Open tool Browser-onlyCosine law angle
Find an angle from three triangle sides.
Open tool Browser-onlySine law side
Find a corresponding triangle side from one side and two angles.
Open tool Browser-onlySine wave
Evaluate a sinusoid from amplitude, frequency, time and phase.
Open tool Browser-onlyAngular to linear speed
Convert angular speed at a radius into tangential speed.
Open tool Browser-onlyPolar to Cartesian
Convert a radius and angle into x and y coordinates.
Open tool Browser-onlyCartesian to polar
Convert x and y coordinates into radius and direction.
Open tool Browser-onlyBearing components
Resolve a distance along a compass bearing into north and east components.
Open tool Browser-onlyPopulation variance
Calculate population variance for six observations.
Open tool Browser-onlyQuartiles
Find lower quartile, median and upper quartile for six values.
Open tool Browser-onlyInterquartile range
Calculate the middle-50-percent spread for six values.
Open tool Browser-onlyRoot mean square
Calculate the quadratic mean of six values.
Open tool Browser-onlyGeometric mean
Calculate the geometric mean of six positive values.
Open tool Browser-onlyHarmonic mean
Calculate the harmonic mean of six positive rates.
Open tool Browser-onlyCoefficient of variation
Compare population standard deviation with the mean for six values.
Open tool Browser-onlyCovariance
Calculate population covariance for three paired observations.
Open tool Browser-onlyPearson correlation
Calculate Pearson's correlation coefficient for three pairs.
Open tool Browser-onlyLinear regression
Fit a least-squares line to three paired observations.
Open tool Browser-onlyProbability complement
Calculate the probability that an event does not occur.
Open tool Browser-onlyIndependent event union
Calculate the chance that at least one of two independent events occurs.
Open tool Browser-onlyConditional probability
Calculate P(A given B) from the intersection and conditioning event.
Open tool Browser-onlyExpected value
Calculate the weighted mean of three possible outcomes.
Open tool Browser-onlyBinomial exact probability
Calculate exactly k successes in n independent equal-probability trials.
Open tool Browser-onlyBinomial mean and variance
Calculate expected successes, variance and standard deviation.
Open tool Browser-onlyPoisson probability
Calculate the probability of exactly k events at an average rate λ.
Open tool Browser-onlyBayes theorem
Update a prior probability after a positive observation.
Open tool Browser-onlyQuadratic derivative
Differentiate ax²+bx+c and evaluate its slope.
Open tool Browser-onlyExponential derivative
Differentiate Ae^(kx) at a selected x.
Open tool Browser-onlyLogarithm derivative
Evaluate the derivative of A ln(x) at positive x.
Open tool Browser-onlyQuadratic tangent line
Find slope and intercept of a tangent to ax²+bx+c.
Open tool Browser-onlyQuadratic average rate
Calculate secant slope of a quadratic over an interval.
Open tool Browser-onlyDefinite linear integral
Integrate mx+b over a finite interval.
Open tool Browser-onlyDefinite quadratic integral
Integrate ax²+bx+c over a finite interval.
Open tool Browser-onlyTrapezoidal rule
Approximate an integral from two endpoint function values.
Open tool Browser-onlySimple interest
Calculate linear interest growth without compounding.
Open tool Browser-onlyCompound interest
Calculate periodic compound growth.
Open tool Browser-onlyContinuous compounding
Calculate exponential growth under continuous compounding.
Open tool Browser-onlyDoubling time
Calculate time required to double under continuous exponential growth.
Open tool Browser-onlyExponential half-life
Calculate half-life from a positive continuous decay-rate magnitude.
Open tool Browser-onlyRequired growth rate
Find the periodic compound rate needed to move from a start to a target value.
Open tool Browser-onlyPrime checker
Determine whether a positive whole number is prime.
Open tool Browser-onlyDivisor count
Count the positive divisors of a whole number.
Open tool Browser-onlySum of divisors
Add every positive divisor of a whole number.
Open tool Browser-onlyEuler totient
Count positive integers up to n that are coprime with n.
Open tool Browser-onlyModular exponentiation
Calculate base^exponent modulo m without constructing the full power.
Open tool Browser-onlyQuadratic vertex
Find the vertex and axis of symmetry of ax²+bx+c.
Open tool Browser-onlyQuadratic discriminant
Calculate a quadratic's discriminant and classify its real roots.
Open tool Browser-onlyInverse linear function
Invert f(x)=mx+b and evaluate the inverse at y.
Open tool Browser-onlyEllipse eccentricity
Calculate focal distance and eccentricity from semiaxes.
Open tool Browser-onlyGreat-circle distance
Calculate spherical surface distance between two latitude-longitude points.
Open tool Browser-only2×2 matrix addition
Add corresponding entries of two 2×2 matrices.
Open tool Browser-only2×2 matrix multiplication
Multiply two 2×2 matrices in order A times B.
Open tool Browser-onlyMatrix–vector product
Apply a 2×2 linear transformation to a two-component vector.
Open tool Browser-onlyMatrix trace
Calculate trace, determinant and eigenvalue sum for a 2×2 matrix.
Open tool Browser-onlyMatrix scalar multiplication
Multiply every entry of a 2×2 matrix by one scalar.
Open tool Browser-onlyNormal CDF
Estimate the probability below a value in a normal distribution.
Open tool Browser-onlyNormal interval probability
Estimate probability between two bounds in a normal distribution.
Open tool Browser-onlyMean confidence interval
Calculate a z-based confidence interval for a mean with known standard deviation.
Open tool Browser-onlyNewton square-root step
Perform one Newton iteration toward the square root of a positive number.
Open tool Browser-onlySimpson's rule
Approximate an integral from endpoint and midpoint function values.
Open toolBirth signs6 tools⌄
Birth sign map
Create a cross-cultural birth-sign map from a date, including Western, Chinese, numerology and calendar results.
Open tool Browser-onlyWestern zodiac
Find a tropical Western sun sign, element and modality from a birth date.
Open tool Browser-onlyChinese zodiac
Find the Chinese zodiac animal, five-element stem and Yin or Yang using the Chinese calendar year.
Open tool Browser-onlyLife path number
Calculate the common numerology life-path and birthday numbers, preserving master numbers 11, 22 and 33.
Open tool Browser-onlyBirthday facts
Find the birth weekday, day of year, traditional birthstone and birth flower.
Open tool Browser-onlyCompare two maps
Compare two cross-cultural birth-sign maps side by side without uploading either birth date.
Open toolInternational business4 tools⌄
Meeting preparation
Turn a country starting point and declared preferences into a practical international meeting plan.
Open tool Browser-onlyPreference profile
Create a transparent work-style profile covering hierarchy, relationships, communication, pace and formality.
Open tool Browser-onlyRepresentative fit
Compare representatives against a client’s declared preferences and relevant cultural capabilities.
Open tool Browser-onlyBusiness checklist
Generate a concise pre-meeting checklist for an international business conversation.
Open toolLocal first
Basic calculations happen entirely inside your browser.
Built for phones
Large controls, clear results and no clutter between them.
Plain answers
Useful formulas and explanations without unnecessary jargon.
Clear answers
About MW SysArc utilities
Are MW SysArc utilities free to use?
Yes. The public calculators and counters in this collection are free to use without creating an account.
Does MW SysArc store my calculator inputs?
No. Basic calculations run locally in your browser, and MW SysArc does not receive or store what you enter.
Can I use a tool result as professional advice?
Use results as practical estimates or educational references. Important financial, legal, medical or business decisions should be checked with qualified sources.