Number Base Converter

Binary, octal, decimal, hexadecimal and base 36 — convert integers of any size in one click.

About this tool

Programmers bounce between number bases daily: hex colors, binary flags, base-36 short IDs. Paste a value in any base from 2 to 36 and this converter shows it in binary, octal, decimal, hexadecimal and base 36 at once — using BigInt, so numbers far beyond the 64-bit limit convert without losing precision.

How to use it

  1. Choose which base your input is in (2, 8, 10, 16 or 36).
  2. Enter the number — spaces and underscores are ignored — and click Convert.
  3. Copy any of the five results.

Good to know

  • Arbitrary precision: numbers with hundreds of digits convert exactly.
  • Negative numbers are supported; fractional values are not (integers only).
  • Base 36 uses digits 0–9 and letters a–z — the largest base that stays unambiguous with a case-insensitive alphabet.