Number Base Converter

The Number Base Converter translates whole numbers from one positional base to another — anything from binary (base 2) up to base 36, where the digits run 0–9 then a–z.

Pick a source base, paste a value, and read the result in your chosen target base alongside instant binary, octal, decimal and hexadecimal equivalents.

Programmers reach for base conversion constantly: reading a hex colour or memory address, decoding a bitmask, or checking what 0b1010 means in plain decimal.

Doing it by hand is error-prone, and many online converters quietly overflow on large values.

This tool uses arbitrary-precision arithmetic under the hood, so a sixty-digit decimal converts to hex without losing a single digit.

Input is case-insensitive, a leading minus sign is preserved, and every digit is validated against the source base so an out-of-range character is caught immediately rather than producing a silently wrong answer.

Like every My Tools Garage utility it runs entirely in your browser.

Nothing is uploaded, nothing is logged, and it keeps working offline once the page has loaded — handy when you are deep in a debugger and just need a quick, trustworthy conversion.