Number Base Converter
Enter a whole number in any base and see it in binary, octal, decimal and hexadecimal at once. Uses arbitrary-precision arithmetic, so there's no upper limit, and binary is grouped into nibbles for readability.
Number
Input base
Binary1010 0000 0000
Octal5000
Decimal2560
HexA00
Value fits in 12 bits. Arbitrary size is supported — the result uses BigInt, so there is no 253 limit. All in your browser.
FAQ
- Can I paste a 0x or 0b prefix?
- Yes — a leading 0x, 0b or 0o is stripped automatically. Pick the matching input base.
- Is there a size limit?
- No. The conversion uses BigInt, so numbers far beyond 2⁵³ convert exactly.
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Free to use, no sign-up. Calculations run in your browser — nothing you type is sent to a server. These tools are for general information only, not professional advice. See the full tool list.