Number base converter

Convert between binary, octal, decimal and hexadecimal — arbitrary precision, so 64-bit values and beyond stay exact.

This tool runs entirely in your browser — nothing you type or open here is ever uploaded. You can disconnect from the internet after the page loads and it still works.

Number

Input base

Binary (base 2)

11111111

Octal (base 8)

377

Hexadecimal (base 16)

📕

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