Binary, decimal and hexadecimal converter

Type in any base and get the number in binary, octal, decimal and hexadecimal at once.

How it works

Each base uses a different number of symbols: binary 2 (0 and 1), octal 8, decimal 10 and hexadecimal 16 (0–9 and A–F). Type in any field and the rest update.

Frequently asked questions

What is FF in decimal?

255: 15 × 16 + 15.

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Length — Metres, kilometres, inches, feet, miles and more.
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Volume — Litres, millilitres, cubic metres, gallons, cups and spoons.
Area — Square metres, hectares, acres, square feet and more.
Speed — km/h, m/s, miles per hour and knots.
Time — Seconds, minutes, hours, days, weeks, months and years.
Digital data — Bytes, KB, MB, GB, TB and their binary versions (KiB, MiB…).
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Energy — Joules, calories, kilocalories, kWh and BTU.
Fuel economy — L/100 km, km/L and miles per gallon (US and UK).