All calculators
We are adding calculators a few at a time, each one checked and tested before it goes live.
Gravel CalculatorWork out how much gravel you need in cubic yards or cubic metres, with an optional weight estimate.OpenTile CalculatorHow many tiles and boxes you need for a floor or wall, including grout joints and extra for cuts.OpenConcrete Slab CalculatorConcrete volume for a slab or pad in cubic yards or cubic metres, plus the number of premixed bags.OpenPaint CalculatorWall area and the gallons or litres of paint for a room, minus doors and windows.OpenMulch CalculatorHow much mulch your beds need in cubic yards or cubic metres, and how many bags to buy.OpenGravel Driveway CalculatorGravel for a driveway built in layers, with the volume and optional weight of each layer.OpenConcrete Volume CalculatorConcrete for footings, walls, round columns, hollow tubes and solid stairs, in cubic yards or cubic metres, plus bags.OpenFlooring CalculatorFloor area for one or more rooms with extra for waste, the boxes of flooring to buy and the total cost.OpenDrywall CalculatorHow many drywall sheets you need for a room or a run of walls, minus doors and windows, with the ceiling if you like.OpenRoofing CalculatorRoof area from the footprint and pitch, in square feet, square metres and roofing squares, plus shingle bundles.Open
Percentage CalculatorPercent of a number, what percent one number is of another, percentage change, and adding or removing a percentage.OpenGPA CalculatorGrade point average from letter grades and credits on the 4.0 scale, with an optional cumulative GPA.OpenFraction CalculatorAdd, subtract, multiply and divide fractions and mixed numbers exactly, simplify a fraction, or turn a decimal into one.OpenRatio CalculatorSimplify a ratio, solve a proportion such as 3 : 4 = 9 : ?, or divide a total in a ratio, exactly.OpenAverage CalculatorMean, median, mode, range and standard deviation of a list of numbers, with the list sorted.OpenArea CalculatorArea and perimeter of rectangles, triangles, circles, ellipses, trapezoids and more, in any unit, with conversions.OpenVolume CalculatorVolume and surface area of cubes, boxes, cylinders, spheres, cones, pyramids and prisms, in litres, gallons and more.OpenProbability CalculatorThe probability and odds of an event, of two independent events together, or of successes over repeated tries.OpenEquation SolverSolve linear and quadratic equations and pairs of linear equations exactly, with square roots, complex roots and the working.OpenScientific CalculatorAn online scientific calculator with trigonometry in degrees or radians, powers, roots, logarithms and factorials.Open
Loan CalculatorMonthly payment, total interest and a year-by-year schedule for a fixed-rate loan, with optional extra payments.OpenCompound Interest CalculatorHow savings grow with compound interest, with regular deposits, any compounding frequency and a yearly table.OpenSavings CalculatorHow much to save each month to reach a goal by a deadline, or how long a goal takes at a set monthly amount.OpenMortgage CalculatorMonthly mortgage payment from the home price, down payment, rate and term, with property tax, insurance and a yearly schedule.OpenDebt Payoff CalculatorWhen you will be debt-free paying several debts from one monthly budget, comparing the avalanche and snowball methods.OpenInvestment Return CalculatorThe gain, total return and annualised return (CAGR) on an investment, including dividends or other income received.OpenSalary CalculatorConvert pay between hourly, daily, weekly, every two weeks, twice a month, monthly and yearly amounts.OpenBudget CalculatorA monthly budget from your income and spending, with what is left over, your savings rate and a 50/30/20-style split.OpenTax CalculatorIncome tax from the brackets you enter, with effective and marginal rates, or sales tax and VAT added or removed.Open
Date CalculatorCount the days, weeks and weekdays between two dates, or add and subtract days, weeks, months and years.OpenAge CalculatorExact age in years, months and days, with totals in months, weeks and days and the next birthday.OpenTime Duration CalculatorThe time between two dates and times, a time plus or minus a duration, or the total of a list of durations.OpenCountdown CalculatorA live countdown in days, hours, minutes and seconds to any date and time, with weeks and weekdays to go.OpenBusiness Days CalculatorCount working days between dates or find a date N business days away, with your own weekend and holidays.OpenTime Zone CalculatorConvert a date and time between any two time zones, with daylight saving time and the difference between them.Open
BMI CalculatorBody mass index from height and weight in metric or US units, with the WHO adult category and its limits explained.OpenBMR CalculatorBasal metabolic rate from the Mifflin-St Jeor, Harris-Benedict and Katch-McArdle equations, side by side.OpenTDEE CalculatorTotal daily energy expenditure: the calories you use in a day, from your BMR and activity level.OpenBody Fat CalculatorEstimate body fat percentage from height and neck, waist and hip measurements with the US Navy method.OpenPace CalculatorRunning pace and speed from distance and time, a finish time from a pace, or the distance, with even splits.OpenHeart Rate Zone CalculatorFive training heart rate zones from your age or measured maximum, as a % of maximum or from heart rate reserve.OpenCalorie CalculatorDaily calories to maintain your weight, or a target with a reduction or increase you choose, with clear warnings.OpenOne Rep Max CalculatorEstimate your one rep max from a set of reps with the Epley and Brzycki formulas, and the weight for other rep counts.Open
Time Card CalculatorAdd up weekly hours from start and end times and breaks, with optional pay and overtime.OpenFreelance Rate CalculatorThe hourly and day rate you need to cover your target income, business costs, fees and an optional tax reserve.OpenBillable Hours CalculatorHow many hours you need to bill at your rate to reach a target income after expenses, fees and an optional tax reserve.OpenProject Pricing CalculatorA fixed project price from estimated hours, your rate, a buffer for overruns, expenses and fees, with an optional deposit.OpenFreelance Day Rate CalculatorConvert an hourly rate to a day rate, or a day rate to hourly, and see what it adds up to each week, month and year.OpenFreelance Income CalculatorWhat you keep from your rate and billable hours after fees, business expenses and an optional tax reserve.OpenInvoice CalculatorInvoice totals from line items, with a discount, the tax rate you enter and payments already received.OpenRetainer CalculatorA monthly retainer fee from hours and rate, with an optional discount, contract value and effective rate if not all hours are used.OpenProfit Margin CalculatorProfit margin from a cost and a price, the price needed for a target margin, or the most an item may cost.OpenMarkup CalculatorThe selling price from a cost and a markup, or the markup from a cost and a price, with the matching profit margin.OpenBreak-Even CalculatorHow many units you need to sell to cover fixed costs, the sales for a target profit, and the margin of safety.OpenDiscount CalculatorThe price after a discount, with an extra percent off and sales tax, the percent off between two prices, or the original price.OpenCost Per Unit CalculatorWhat each unit costs from fixed and variable costs, how it falls with volume, and the profit at a selling price.OpenHourly Wage CalculatorYour hourly wage from yearly, monthly or weekly pay, and your real rate per hour worked with unpaid hours and paid time off.OpenBusiness Revenue CalculatorRevenue from your products and services per week, month, quarter or year, after returns, with a growth projection.OpenStartup Cost CalculatorHow much money you need to start a business: one-time costs, months of running costs and a contingency.OpenCash Flow CalculatorProject your cash balance month by month and see if and when the money runs out.OpenOvertime CalculatorOvertime and total pay from your hourly rate, hours and the multiplier that applies to you, such as time and a half.OpenWork Hours CalculatorWorking hours per day, week, month and year from your schedule, breaks and days off, with a full-time share.OpenConversion Rate CalculatorConversion rate from visitors and conversions, expected conversions, or the visitors you need, with value per visitor.OpenROI CalculatorReturn on investment for a project or campaign as a percentage, with an annualised rate and the return needed for a target.OpenROAS CalculatorReturn on ad spend as a ratio and percentage, with profit after ads and the break-even ROAS for your margin.OpenCAC CalculatorCustomer acquisition cost from your sales and marketing costs, with payback period and LTV to CAC ratio.OpenPayroll CalculatorGross and take-home pay per paycheck from a salary or hourly rate, with the deductions you enter.OpenEmployee Cost CalculatorThe full yearly cost of an employee: salary plus employer taxes, benefits and other costs, per month and per hour.Open
Data Storage ConverterConvert between bits, bytes, KB, MB, GB, TB and the binary KiB, MiB, GiB and TiB, and see why 1 TB shows as 931 GB.OpenDownload Time CalculatorHow long a file takes to download at a connection speed, or the speed you need to download it in time.OpenPPI CalculatorPixel density of a screen from its resolution and diagonal, with its width, height, dot pitch and aspect ratio.OpenAspect Ratio CalculatorFind the aspect ratio of any size, or the missing width or height to resize an image or video to a ratio.OpenBinary CalculatorConvert between binary, octal, decimal and hexadecimal, and add, subtract, multiply, divide or AND, OR, XOR numbers.OpenSubnet CalculatorNetwork and broadcast addresses, host range and host count for an IPv4 address with a prefix or subnet mask.OpenBandwidth CalculatorHow much data a connection moves in an hour, day or 30 days, or how much bandwidth a website needs for its traffic.OpenImage Size CalculatorThe uncompressed size of an image from its pixels and colour depth, its megapixels, and its print size at a DPI.OpenScreen Resolution CalculatorA screen’s width, height and area from its diagonal and aspect ratio, a size comparison, and the resolution for a pixel density.Open
Tip CalculatorWork out the tip and total, and split the bill evenly between any number of people.OpenFuel Cost CalculatorThe fuel and cost of a trip from distance, fuel economy and price, in km or miles, L/100 km or mpg, split between passengers.OpenTravel Budget CalculatorA trip budget from accommodation, daily costs and travel, with a buffer, per person and per day.OpenPacking Weight CalculatorAdd up your luggage item by item and see how it compares with your baggage allowance, in kg or lb.OpenDistance CalculatorThe straight-line (great-circle) distance between two places from their coordinates, in km, miles and nautical miles.OpenSpeed CalculatorSpeed, distance or travel time from the other two, in km/h, mph, m/s, knots or ft/s.OpenUnit ConverterConvert length, weight, volume, area, speed, time and temperature between metric, US and imperial units.OpenCooking Measurement ConverterConvert cups, spoons and millilitres, cups to grams for your ingredient, scale a recipe, and oven temperatures.OpenMoving Cost EstimatorAdd up the cost of a move from your quotes: movers, van, fuel, packing, storage and insurance, with a buffer.Open