Calculators that show their working
Free online calculators for finance, health, maths and everyday conversions. EMI, SIP, BMI, calories, percentages and more — no sign-up, instant results.
88 free calculators across 13 categories.
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All calculators A–ZFinance
Work out EMIs, plan a SIP and see exactly how much interest a loan will cost you before you sign.
- EMI CalculatorWork out the monthly instalment on a home, car or personal loan — and what it costs you in interest.
- SIP CalculatorSee what a monthly mutual fund investment could grow into, and how much of that is returns rather than your own money.
- SCHD Dividend CalculatorProject income from the Schwab US Dividend Equity ETF, with reinvestment, monthly contributions and tax.
- VOO Dividend CalculatorProject dividend income and reinvested growth from Vanguard's S&P 500 ETF over any horizon.
- VYM Dividend CalculatorProject income from Vanguard's High Dividend Yield ETF, with reinvestment, contributions and tax.
- DGRO Dividend CalculatorProject income from the iShares Core Dividend Growth ETF, where the growth rate matters more than the starting yield.
Health & Fitness
Track BMI and find the calorie target that matches your body and how active you actually are.
- BMI CalculatorCheck your body mass index against both the international and the Asian cut-offs India actually uses.
- Calorie CalculatorFind how many calories your body burns in a day, and the target to hold, lose or gain weight.
- GFR CalculatorTurn a creatinine result into an eGFR and a CKD stage, using the 2021 race-free equation.
- IVF Due Date CalculatorDue date from your embryo transfer, egg retrieval or IUI, not from a last period you did not have.
- BMR CalculatorYour basal metabolic rate, the calories your body burns at rest, from three formulas side by side.
- Body Fat CalculatorEstimate your body fat percentage from a tape measure, using the US Navy circumference method.
Maths
Everyday arithmetic without the mental gymnastics, with the working shown step by step.
- Percentage CalculatorWork out a percentage of a number, what share one number is of another, or the change between two values.
- Fraction CalculatorAdd, subtract, multiply and divide fractions, with the answer reduced to lowest terms and shown as a decimal.
- Scientific CalculatorTrigonometry, logs, powers, roots and factorials in degrees or radians. Type the whole expression or use the keypad.
- Average CalculatorMean, median, mode, range and standard deviation of any list of numbers. Paste a column straight from a spreadsheet.
- Ratio CalculatorSimplify a ratio to lowest terms, or find the missing number in a proportion such as 16 : 9 = 1280 : ?
- Square Root CalculatorSquare, cube and higher roots, with the simplest radical form such as √72 = 6√2.
Everyday
Quick sums for daily life: splitting a bill, checking a sale price and what a trip will cost in fuel.
- Tip CalculatorWork out the tip and split the bill, with an option to round each share up to a whole dollar.
- Discount CalculatorThe sale price and how much you save, including an extra coupon on top and any tax added at the till.
- Fuel Cost CalculatorWhat a trip will cost in petrol or diesel, one way or return, split between passengers. Kilometres or miles.
Converters
Convert units and currencies, and work out exact ages, date differences and time durations.
- Unit ConverterConvert length, weight and temperature between metric and imperial units.
- Age CalculatorWork out an exact age in years, months and days — and how long until the next birthday.
- Date Difference CalculatorDays between two dates, in years, months and days, weeks, and weekdays, with or without the end date.
- Time Duration CalculatorHours and minutes between two times, overnight shifts included, less a break, in decimal hours for timesheets.
- Currency ConverterConvert between 30 currencies at the European Central Bank's reference rates, with the rate and its inverse.
Weather
Turn a forecast into the answer you actually want — starting with whether school is likely to be called off tomorrow.
Hobbies & Crafts
The small, awkward sums that come up mid-project — paper, tuning, kerf widths and tank chemistry.
- Scrapbook Paper CalculatorHow many sheets a project needs, and which way round to cut them for the least waste.
- Piano Tuning Interval CalculatorFrequency for any note from any reference pitch, in equal temperament or just intonation.
- Waterjet Kerf CalculatorEntry and exit kerf, taper and the tool offset to program, for any material and thickness.
- Shrimp Tank Water CalculatorTarget GH, KH, TDS and pH for your species, and what a water change will actually do to them.
- Yarn Yardage CalculatorHow many skeins a hat, sweater or blanket takes in any yarn weight, knitted or crocheted.
Pets
Feeding portions and husbandry maths by species, from everyday dogs and cats to the exotic pets generic calculators ignore.
- Parrot Feeding CalculatorDaily food by weight for your species — split into pellets, fresh food and the treat ceiling.
- Reptile UVB Distance CalculatorHow far the lamp should sit from the basking spot to hit your species' Ferguson zone.
- Fish Medication Dosing CalculatorDose by actual water volume for common aquarium treatments, at full or reduced strength.
- Dog & Cat Food CalculatorHow much to feed by species, weight and life stage, in cups and grams of your actual food.
Construction & DIY
Order the right amount of concrete, gravel, shingles, paint, tile, drywall, fencing and sod the first time, with the waste allowances contractors actually use, plus stair layouts and air conditioner sizing.
- Asphalt CalculatorTons of hot-mix asphalt for a driveway, path or parking area, with waste and delivered cost.
- Rebar CalculatorBars, lap splices, weight and sticks to buy for a slab, footing or deck grid.
- Concrete CalculatorCubic yards of ready-mix for slabs, footings, grade beams, columns and caissons, with waste and cost.
- Concrete Bag CalculatorHow many 40, 60 or 80 lb bags of premix concrete for a pad, a set of post holes or a known volume.
- Gravel CalculatorTons and cubic yards of crushed stone, pea gravel or road base for a driveway, path or slab sub-base.
- Roof Pitch CalculatorRoof pitch from rise and run or an angle, and the roof area, squares and shingle bundles for a house.
Freight & Logistics
Density, cube and billable weight worked out before the carrier does it for you, so a quote does not turn into a reclass invoice.
- Freight Class CalculatorLTL freight density and NMFC class from pallet dimensions and weight, on the 2025 scale or the legacy 18-class table.
- CBM CalculatorCubic metres for a shipment of cartons, and how many fit in a 20 ft, 40 ft or 40 ft high-cube container.
- Dimensional Weight CalculatorDIM weight and billable weight for UPS, FedEx, USPS, express and air freight: see which one the carrier will charge.
Sports
Pitching stats, golf handicap differentials and fantasy football scoring, worked out the way the official rules do it.
- ERA CalculatorEarned run average and WHIP, reading innings the way a box score writes them.
- Fantasy Football Points CalculatorScore any stat line in PPR, half PPR and standard leagues, side by side.
- Golf Handicap CalculatorScore differential, course handicap and net score under the World Handicap System.
Education
Know exactly what you need on the final before you walk into the exam room.
Legal & Payroll
Rough, transparent estimates for paychecks and injury claims — the starting point for a conversation with a payroll provider or lawyer, never a replacement for one.