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FreeBigInt readyPrivate (client-side)

Number Base Converter

Convert between binary, octal, decimal and hexadecimal — instantly, for numbers of any size. Paste a value, pick its base, and see all four representations update live.

Binary11111111
Octal377
Decimal255
HexadecimalFF

How it works

Every value has multiple equivalent notations. 255 (decimal) is 11111111 in binary, 377 in octal and FF in hexadecimal. This converter parses your input as an integer in the chosen base and re-renders it in all four — using BigInt under the hood, so it also handles enormous numbers like full-length Ethereum addresses and 256-bit hashes.

Common uses

Developers convert between bases constantly: subnet masks and permissions (decimal ↔ octal), colors (decimal ↔ hex), bit flags (binary ↔ hex), and cryptographic material (hex ↔ binary). With this tool you never need to switch mental gears — just paste and read.

Is it private?

Yes — conversion happens entirely in your browser. Nothing is uploaded, stored or logged.