Number Base Converter

Binary · octal · decimal · hex. BigInt-safe — works on arbitrarily large numbers.

Equivalents

Binary (base 2)

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Octal (base 8)

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Decimal (base 10)

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Hexadecimal (base 16)

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Why these four bases

  • Binary (2) — everything in a computer is binary at the lowest level.
  • Octal (8) — three binary digits at a time. File permissions on Unix (chmod 755) are octal.
  • Decimal (10) — what humans count in.
  • Hexadecimal (16) — four binary digits at a time, compact for representing bytes (00–FF). Memory addresses, color codes, MAC addresses all use hex.

Big numbers

This converter uses JavaScript's BigInt, so you can convert numbers far larger than the standard 64-bit limit. A 256-bit hash? No problem.