Calculators
Everyday calculators that show their working, so you can see exactly how each answer was reached.
Everyday maths
- Percentage calculatorPercent of, percent change, increase and decrease
- Online calculatorBasic and scientific calculator
- Fraction calculatorAdd, subtract, multiply and divide
- Average calculatorMean, median, mode and more
- Discount calculatorSale price after a percentage off
- Tip calculatorWork out the tip and split the bill
- Ratio calculatorSolve or simplify a ratio
- Unit price calculatorWhich pack is cheaper per unit
Money and finance
- Credit card payoff calculatorMonths to pay off a card, and interest
- Debt payoff calculatorSnowball or avalanche payoff plan
- Savings goal calculatorMonthly saving to reach a goal
- Retirement calculatorSavings at retirement and income
- Inflation calculatorWhat old dollars are worth today
- APR to APY calculatorConvert APR and APY both ways
- APY to APR calculatorConvert APY to the nominal APR
- Future value calculatorWhat money grows to over time
- Present value calculatorWhat future money is worth today
- NPV and IRR calculatorNet present value and IRR
- Rent affordability calculatorRent you can afford on your income
- House affordability calculatorHome price you can afford
- Car payment calculatorMonthly car payment with tax and trade-in
- EMI calculatorLoan EMI with amortisation table
- SIP calculatorSIP maturity value with step-up
- FD calculatorFixed deposit maturity and interest
- GST calculatorAdd or remove GST, with CGST and SGST
- Compound interest calculatorSavings growth with monthly deposits
- Derivative calculatorDerivatives with the rules used
- Hourly to salary calculatorHourly wage as yearly pay
- Loan calculatorMonthly payment and total interest
- Mortgage calculatorMonthly payment with tax and insurance
- Profit margin calculatorMargin and markup from cost and price
- Reverse sales tax calculatorPrice before tax from a total
- ROI calculatorReturn on investment and CAGR
- Salary to hourly calculatorYearly pay as an hourly rate
- Sales tax calculatorAdd or remove tax from a price
- Simple interest calculatorInterest from amount, rate and time
- VAT calculatorAdd or remove VAT at any rate
Business and pay
Dates and time
- Age calculatorExact age in years, months and days
- Dog age calculatorDog years to human years
- Cat age calculatorCat years to human years
- Days between datesCount days, weeks and weekdays
- Business days calculatorWorking days between dates
- Date calculatorAdd or subtract days from a date
- Days untilCountdown in days to any date
- Days until ChristmasCountdown to Christmas Day
- Days until HalloweenCountdown to 31 October
- Days until ThanksgivingCountdown to US Thanksgiving
- Days until New YearCountdown to 1 January
- Days until EasterCountdown to Easter Sunday
- Day of the week calculatorWhat day of the week any date was
- Week numberCurrent ISO and US week number
- Printable calendarMonthly or yearly calendar to print
- Hours calculatorHours worked between two times
- Time duration calculatorDuration between two times
- Add time calculatorAdd hours and minutes to a time
- Time to decimal calculatorHours and minutes to decimal hours
- Decimal to time calculatorDecimal hours to hours and minutes
- Military time converterMilitary time to 12-hour and back
- Leap year checkerIs it a leap year?
- Julian date converterDates to YYDDD and Julian Day
- Zodiac sign calculatorYour star sign from your birthday
- Chinese zodiac calculatorYour Chinese zodiac animal
Time zones
- Time zone converterConvert times between time zones
- AEST to EST converterSydney time to Eastern Time
- AEST to IST converterSydney time to India time
- CET to EST converterCentral Europe to Eastern Time
- CET to IST converterCentral Europe to India time
- CST to EST converterCentral Time to Eastern Time
- CST to PST converterCentral Time to Pacific Time
- EST to CET converterEastern Time to Central Europe
- EST to CST converterEastern Time to Central Time
- EST to GMT converterEastern Time to UK time
- EST to IST converterEastern Time to India time
- EST to MST converterEastern Time to Mountain Time
- EST to PST converterEastern Time to Pacific Time
- EST to UTC converterEastern Time to UTC
- GMT to EST converterUK time to Eastern Time
- GMT to IST converterUK time to India time
- GMT to PST converterUK time to Pacific Time
- IST to EST converterIndia time to Eastern Time
- IST to GMT converterIndia time to UK time
- IST to PST converterIndia time to Pacific Time
- IST to UTC converterIndia time to UTC
- JST to EST converterJapan time to Eastern Time
- MST to EST converterMountain Time to Eastern Time
- PST to CST converterPacific Time to Central Time
- PST to EST converterPacific Time to Eastern Time
- PST to GMT converterPacific Time to UK time
- PST to IST converterPacific Time to India time
- PST to UTC converterPacific Time to UTC
- UTC to EST converterUTC to Eastern Time
- UTC to IST converterUTC to India time
- UTC to PST converterUTC to Pacific Time
Health and fitness
- BMI calculatorBody mass index in kg or lb
- Calorie calculatorDaily calories, BMR and TDEE
- Body fat calculatorBody fat % from tape measurements
- Sleep calculatorBedtimes and wake times by sleep cycle
- Due date calculatorPregnancy due date from your last period
- Pace calculatorRunning pace per km or mile
- BMR calculatorCalories you burn at rest
- Macro calculatorProtein, carbs and fat in grams
- Ideal weight calculatorIdeal body weight for your height
- Water intake calculatorHow much water to drink a day
- Calories burned calculatorCalories burned by activity
- Heart rate zone calculatorTraining zones from your age
- One rep max calculatorYour 1RM from any set
- Steps to miles calculatorSteps to miles or km by height
- Miles to steps calculatorHow many steps in a mile or km
- Ovulation calculatorFertile window and ovulation date
- Pregnancy week calculatorHow many weeks pregnant you are
- Conception date calculatorEstimate when you conceived
- Waist-to-hip ratio calculatorWaist-to-hip ratio with WHO cut-offs
- Lean body mass calculatorLean body mass from height and weight
Home, travel and energy
- Square footage calculatorArea in sq ft, m² and sq yd
- Concrete calculatorConcrete volume and bags for a slab
- Electricity cost calculatorRunning cost of any appliance
- Fuel cost calculatorGas or petrol cost for a trip
- Speed distance time calculatorSolve for speed, distance or time
- Paint calculatorPaint needed for a room
- Tile calculatorTiles and boxes for a floor or wall
- Flooring calculatorFlooring area, boxes and cost
- Gravel and mulch calculatorGravel or mulch in yards, tonnes, bags
- Wallpaper calculatorRolls of wallpaper for a room
- Fence calculatorPosts, rails and pickets for a fence
- BTU calculatorAir conditioner BTU for a room
- MPG calculatorFuel economy from a fill-up
- Tire size calculatorCompare tyre sizes and speedo error
Cooking
Maths and science
- Algebra calculatorSolve equations, see the steps
- Fraction to decimalFractions and mixed numbers to decimals
- Decimal to fractionDecimals to simplified fractions
- Significant figures calculatorCount and round sig figs
- Rounding calculatorRound to any place or nearest 10
- Exponent calculatorPowers of any size, exactly
- Square root calculatorSquare roots, simplified radicals
- Cube root calculatorCube roots, negatives included
- Log calculatorLogarithms in any base, ln, log2
- Factorial calculatorExact n! for big numbers
- Permutation and combination calculatornPr and nCr, with or without repeats
- Probability calculatorAnd, or, not and at least once
- Z-score calculatorZ-score, percentile and p-value
- Confidence interval calculatorConfidence interval for a mean
- Sample size calculatorHow many responses you need
- Weighted average calculatorWeighted mean from values and weights
- Matrix calculatorMultiply, inverse, determinant
- Long division calculatorStep-by-step long division
- Slope calculatorSlope and line through two points
- Distance formula calculatorDistance between two points
- Midpoint calculatorMidpoint of a line segment
- Circle calculatorArea, circumference, radius
- Area calculatorArea of common shapes
- Volume calculatorVolume of common solids
- Surface area calculatorSurface area of common solids
- Triangle calculatorSolve any triangle from 3 values
- Binary calculatorArithmetic in binary
- Hex calculatorArithmetic in hexadecimal
- Modulo calculatora mod n, every convention
- Proportion calculatorSolve a/b = c/d for x
- Prime factorization calculatorPrime factors and divisors
- Metric prefixesSI prefixes from quecto to quetta
- Unit circleExact sin, cos, tan of key angles
- Quadratic equation solverRoots of ax² + bx + c = 0
- Pythagorean theorem calculatorMissing side of a right triangle
- GCF and LCM calculatorGreatest common factor and LCM
- Prime number checkerIs it prime, and its prime factors
- Standard deviation calculatorStandard deviation and variance
- Percent error calculatorMeasured vs true value, as a %
- Scientific notation converterScientific, E and engineering notation
- Ohm's law calculatorVolts, amps, ohms and watts
- Watts to amps calculatorWatts, volts and amps, AC or DC
- Resistor color code calculatorResistor bands to ohms and back
- Aspect ratio calculatorRatio of a size, and resize to fit
- Multiplication tableTimes tables up to 20 × 20
- Prime numbers listAll primes up to 10,000
- Graphing calculatorPlot functions, find roots
- System of equations solverSolve linear systems with steps
- Integral calculatorDefinite integrals, area under curves
- Linear regression calculatorLine of best fit, r and r²
- Quartile calculatorQuartiles, IQR and box plot
Science, sun and moon, maps
- Periodic tableAll 118 elements, searchable
- Molar mass calculatorMolar mass from any formula
- Chemical equation balancerBalance chemical equations
- Half-life calculatorRadioactive decay and half-life
- Ideal gas law calculatorSolve PV = nRT
- Sunrise and sunset calculatorSunrise, sunset and twilight times
- Moon phase calculatorMoon phase for any date
- Coordinate converterDecimal degrees ⇄ DMS ⇄ DDM
- Distance between coordinatesDistance and bearing between points
School and grades
- Words to pages calculatorWord count to pages and back
- CGPA to percentage calculatorCGPA to percentage and back
- Final grade calculatorScore you need on the final exam
- GPA calculatorCredit-weighted GPA on a 4.0 scale
- Grade calculatorTest score to percentage and letter
- Grade curve calculatorCurve a list of test scores