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.

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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