Number Base Converter

Convert integers between supported bases. Negative values use a sign prefix in non-decimal output (not two's complement). Paste a value and select from/to bases in Tool Settings.

  • Runs entirely in your browser
  • No data stored or sent to a server
  • Free forever — no signup
  • Instant conversion

Input and Output

Use the interactive encoder and decoder on this page to process your text.

Learn more about Number

How to Convert Numbers Between Bases

Number Base Conversion

When to Convert Number Bases

Convert between decimal, binary, hexadecimal, and octal when debugging low-level code, reading memory addresses, interpreting bitmask flags, or verifying color hex values against decimal RGB components during systems programming and hardware troubleshooting.

Supported Conversions

Enter an integer in one base and convert to another using the From and To selectors in Tool Settings. Supports binary, octal, decimal, hexadecimal, and base-36 — one conversion pair per run.

Developer Tips

  • Prefix hex with 0x in code — the tool accepts common input formats
  • Negative values are shown with a sign prefix in non-decimal bases (not two's complement bit patterns)
  • Use binary view to verify individual flag bits in permission or status masks

Frequently asked questions

Are negative numbers supported?

Yes. A minus sign is preserved in the output. Non-decimal bases show a signed prefix (e.g. -ff in hex), not two's complement bit patterns.

What is the maximum value?

There is no practical limit — conversion uses JavaScript BigInt for arbitrary-precision integers.