Number base converter
Convert between binary, octal, decimal, hex.
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How to use Number base converter
Convert whole numbers between binary, octal, decimal and hexadecimal without rounding large integers.
Step by step
- 1Enter an integer and choose its source base. Optional 0b, 0o and 0x prefixes match the selected base.
- 2Read all four results. Invalid digits produce an error rather than a partial answer.
- 3Try the examples or select an ASCII reference row.
What to expect
- Binary 1010 = decimal 10: 1×8 + 0×4 + 1×2 + 0×1.
- Decimal 255 = hexadecimal FF: 255 = 15×16 + 15.
- 9007199254740993 stays exact. Fractions and scientific notation are not supported.
Common use cases
- Check programming values and learn positional notation.
Privacy & data
Numbers are converted on your device and are not uploaded.
At a glance
| Price | Free |
|---|---|
| Account | Not needed |
| Where it runs | In your browser |
| Watermark or limits | None added |
Frequently asked questions
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