Base Converter

How Base Converter works

Convert a number between bases 2, 8, 10, 16 and 36, with validation for invalid digits. Everything happens inside this page: the tool reads your input, runs the calculation or conversion locally, and hands the result back to you. Nothing is transmitted, because there is no backend to transmit it to.

That design choice is deliberate. Most free tool sites upload your files to a server, process them there, and quietly keep a copy. Toolcin cannot do that — the site is a set of static files. If your connection dropped the moment the page finished loading, every tool would still work.

Any base between 2 and 36

The converter takes a number in one base and expresses it in another, using 0–9 and A–Z for digits beyond nine. Base 2, 8, 10 and 16 are the common ones; base 36 is used for compact identifiers because it fits 36 symbols into alphanumeric characters.

Conversion is exact for integers of any size the browser can hold, so there is no rounding to worry about.

Reading hex without counting

Each hexadecimal digit is exactly four binary bits, so hex is a shorthand for binary: 1100 1010 is CA. Each octal digit is three bits. That is why those bases appear wherever bit patterns matter.

Base 36 has no such relationship — it is purely a compact alphabet, which is why it appears in short URLs rather than in memory dumps.

What it does not handle

Fractions and negative numbers are not converted; the input is treated as a non-negative integer. A leading 0x is accepted for hex, but other prefixes are not.

Good to know

• Works offline once loaded, including on flights and in locked-down networks.
• No file size limit beyond your device's own memory.
• Free to use, with no account and no usage counter.
• Results are produced locally, so they are not logged or shared with anyone.

Questions