Number base converter

Binary

0b11111111

Octal

0o377

Decimal

255

Hexadecimal

0xff

About this tool

Type a number, pick its base and see it in all four systems at once. Very large numbers work too because the tool uses arbitrary-precision integers.

🔒 Your input stays in your browser and is never sent anywhere.

How do I convert hex to decimal?

Choose Hexadecimal as the input base and enter the value, for example ff. The decimal result (255) appears instantly.

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