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Unit converters

Length, weight, temperature, cooking, clothing sizes, and more. 9 tools · free, no sign-up

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Most popular

Length ConverterMillimetres to inches, metres to feet, kilometres to miles — every unit at once.Weight ConverterKilograms, pounds, stones, ounces, and grams, converted together.Cooking ConverterCups to grams for flour, sugar, butter, and more.

All Units tools9

cm→inLength ConverterMillimetres to inches, metres to feet, kilometres to miles — every unit at once.kg→lbWeight ConverterKilograms, pounds, stones, ounces, and grams, converted together.ml→flozVolume ConverterLitres, gallons, pints, and fluid ounces — US and UK.°C→°FTemperature ConverterCelsius to Fahrenheit and back, plus Kelvin.cup→gCooking ConverterCups to grams for flour, sugar, butter, and more.mb→gbData Storage ConverterMB, GB, and TB — and why your drive shows less than you paid for.us→euShoe Size ConverterUS, UK, EU, and Japanese shoe sizes.uk→euClothing Size ConverterUS, UK, and EU clothing sizes, with real measurements.px→16:9Aspect Ratio CalculatorFind the ratio of any screen or image size, like 16:9.

About these tools

Inches to centimetres, kilos to pounds, Celsius to Fahrenheit, cups to grams, your shoe size in Europe — all the everyday conversions, in one place, with answers as you type.

The numbers are exact. An inch is exactly 2.54 cm and a pound exactly 0.45359237 kg by international agreement, and every converter uses those official figures.

Where the answer depends on something, we show it rather than guess. A cup of flour weighs much less than a cup of honey, so the cooking converter asks for the ingredient. A US gallon is 20% smaller than a UK one, so both are listed. Shoe and clothing sizes vary by brand, so you see the whole chart.

Questions people ask

Are these conversions exact?

Yes, wherever an official definition exists — inches, pounds, litres, and bytes all have one. Ingredient weights and size charts are averages, and they’re marked as such.

Why do I have to pick an ingredient to convert cups to grams?

A cup measures space, not weight. A cup of flour is 125 g, but a cup of honey is 340 g.

Is a US gallon the same as a UK gallon?

No. A US gallon is 3.785 litres and a UK (imperial) gallon is 4.546 — about 20% bigger.

Why does my 1 TB drive show as 931 GB?

Your computer counts in a slightly different unit but still calls it “GB”. Nothing is missing. The data storage converter shows both numbers.

Can I trust the shoe and clothing size charts?

As a starting point. Brands can differ by a whole size, so measuring yourself is the most reliable option.