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Number Base Converter

Convert numbers between binary, octal, decimal and hexadecimal.

  • Free
  • No sign-up
  • Runs in your browser
Binary (base 2)
11111111
Octal (base 8)
377
Decimal (base 10)
255
Hexadecimal (base 16)
FF
Base 36
73

Everything you type is processed in your browser. Nothing you enter is sent to our servers or stored by us.

How to use the Number Base Converter

  1. Type a number.
  2. Choose the base it's written in.
  3. Read it in every other base.

What does this tool do?

Computers work in binary (base 2), and developers often use hexadecimal (base 16) as a compact way to write binary. Conversions use exact big-integer arithmetic, so even very long numbers convert without rounding.

Why use it?

  • Read memory addresses, colors and bit flags.
  • Computer science homework.
  • Exact for numbers of any size.

Example

255 in decimal is 11111111 in binary, 377 in octal and FF in hexadecimal.

Privacy

Everything you type is processed in your browser. Nothing you enter is sent to our servers or stored by us. There's no account to create and nothing to install.

Last reviewed by the M2Toolkit team.

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