Guides

Practical conversion how-tos, no fluff.

Clear, step-by-step guides to the conversions people actually look up: cm to inches, kg to pounds, Celsius to Fahrenheit, MB to GB and more. Each one is backed by a free converter that runs entirely in your browser.

Clothing Size 5 min

How to Convert Clothing Sizes (US, UK, EU)

See how US, UK, EU and international sizes line up for tops, dresses and jeans, and why to treat any conversion as a guide.

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Number Base 5 min

How to Convert Binary to Decimal (and Back)

Convert binary to decimal by hand with place values, plus the quick doubling method and the reverse.

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Temperature 4 min

How to Convert Celsius to Fahrenheit (and Back)

Convert Celsius to Fahrenheit with the formula and a quick mental shortcut, plus the point where they meet.

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Length 4 min

How to Convert cm to Inches (and Back)

Convert centimetres to inches with the exact 2.54 factor, plus a mental shortcut for quick estimates.

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Weight 4 min

How to Convert kg to Pounds (and Back)

Convert kilograms to pounds with the exact factor, plus a quick shortcut and how stone fits in.

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Data Storage 4 min

How to Convert MB to GB (and Why It Is Confusing)

Convert MB to GB, and learn the decimal-versus-binary difference behind 'missing' drive space.

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Volume 4 min

How to Convert ml to Cups for Cooking

Convert millilitres to cups for recipes, and learn why a cup is not the same size everywhere.

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Fuel Economy 4 min

How to Convert MPG to L/100km (and Back)

Convert MPG to L/100km, and understand why it is an inverse conversion rather than a simple multiply.

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Speed 4 min

How to Convert mph to km/h (and Back)

Convert mph to km/h with the exact factor and a fast shortcut, plus the common speed-limit equivalents.

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Pressure 4 min

How to Convert psi to bar for Tyres and More

Convert psi to bar with the exact factor, plus the tyre-pressure equivalents worth knowing.

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Roman Numerals 5 min

How to Write Roman Numerals (Numbers to Roman)

Learn the seven letters and the subtraction rule, and write any number or year as a Roman numeral.

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