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Number Base Converter

Convert numbers between binary, octal, decimal, and hexadecimal online with BigInt precision, plus text ↔ hex ASCII conversion. Instant, client-side.

Number converter

Binary

11111111

Octal

377

Decimal

255

Hexadecimal

FF

Text → HEX

486921

HEX → Text

Hi!

How to use

  1. Type the number, pick from/to base (binary, octal, decimal, hex).
  2. Use Text to HEX boxes for ASCII conversion.
  3. Copy the result.

FAQ

How large numbers work?

BigInt is used, so even 128-bit values convert exactly — no float rounding.

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