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Conversions calculators

Convert units exactly and answer practical quantity questions: fuel for a trip, electricity for an appliance, paint for a room, tiles for a floor.

Area Converter Convert area between square metres, square feet, square yards, acres, hectares, square kilometres and square miles Electricity Cost Calculator Calculate what an appliance costs to run from its wattage, hours of use per day, days and your electricity price per kWh Fuel Cost & MPG Calculator Calculate the fuel needed and the cost of a trip from distance, miles per gallon and the price of fuel Length Converter Convert length and distance between metres, kilometres, miles, yards, feet, inches, centimetres and millimetres with exact conversion factors Paint Quantity Calculator Calculate paint needed from room dimensions, coats, coverage per gallon and openings — in gallons, cans and cost Speed Converter Convert speed between miles per hour, kilometres per hour, metres per second, knots and feet per second Temperature Converter Convert between Celsius, Fahrenheit and Kelvin instantly, with the formulas for each direction and a worked example Tile Quantity Calculator Calculate the number of tiles for a floor or wall from the area, tile size, waste allowance and price per square foot Volume Converter Convert volume between litres, millilitres, cubic metres, US gallons, quarts, cups and fluid ounces, with US and imperial differences noted Weight Converter Convert weight between kilograms, pounds, ounces, grams, milligrams and stones using exact conversion factors

What you can calculate

These tools use exact unit definitions where they exist (the inch is exactly 2.54 cm, a US gallon exactly 3.785411784 L) and clearly stated assumptions where they do not (coverage per gallon, real-world fuel economy).

For anything regulated — medication, freight, engineering — use the governing standard's figures rather than these rounded results.

Frequently asked questions

Are these calculators free?

Yes. Every calculator on this site is free, needs no account and runs entirely in your browser.

How accurate are the results?

Each page states its assumptions and shows a worked example. The formulas are standard industry formulas, but real-world results depend on fees, taxes and individual circumstances.

Do you store what I type?

No. The calculation runs in your browser and nothing is submitted to a server.

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