FLIPUNITS

Fast, free and accurate

Unit converter

Convert metres to feet, kilograms to pounds, litres to gallons and more. Every result uses exact unit definitions, and UK and US units are clearly labelled.

Quick converters

Type in either box to convert both ways. Cards with a link have a full page with a table, worked examples and FAQs.

Calculators and guides

Cooking converterCups, spoons, grams and ounces for 14 ingredientsConstruction calculatorsConcrete volume, tiles and roof pitchHealth calculatorsBMI in stones or kg, BMR and running paceCurrency calculatorSee the real cost of a rate and its feesMetric and imperial guideExact definitions, UK v US units and shortcutsCooking cheat sheetGas marks, fan ovens, cups and ounces

Converter pages by category

Length

Metres to feet converterFeet to inches converterCentimetres to inches converterMillimetres to inches converterFeet and inches to centimetresKilometres to miles converterMiles to feet converterMetres to yards converter

Weight

Pounds to kilograms converterOunces to grams converterStones and pounds to kilogramsPounds to ounces converter

Volume

Litres to UK gallons converterLitres to US gallons converterLitres to UK pints converterLitres to US pints converterCups to millilitres converterTablespoons to millilitres converterTeaspoons to millilitres converterMillilitres to fluid ounces converter

Temperature

Celsius to Fahrenheit converterCelsius to kelvin converter

Area

Square metres to square feet converterAcres to hectares converter

Speed

Mph to km/h converterKnots to km/h converter

Fuel economy

MPG to L/100km converter

Pressure

PSI to bar converter

Energy

Calories to kilojoules converter

Frequently asked questions

Are the conversions exact?

They use the exact legal definitions of each unit, such as 1 inch = 2.54 cm and 1 pound = 0.45359237 kg. Results are rounded to a sensible number of decimal places for display.

Which gallon, pint or cup do you use?

UK and US gallons and pints are different sizes, so each converter says which one it uses. The dedicated converter pages let you choose between UK, US and metric versions where it matters.

Can I convert in both directions?

Yes. Type in either box and the other one updates, or use Swap to reverse the units.

Does FlipUnits store what I type?

No. The converters run in your browser and nothing you enter is sent to us.