What is a number base or radix?

A base is how many distinct digit symbols a positional number system uses. Decimal (base 10) uses 0 to 9, binary (base 2) uses 0 and 1, and hexadecimal (base 16) uses 0 to 9 then A to F. The same quantity is written differently in each base but has identical value.

How does base-36 work?

Base-36 uses all ten digits 0 to 9 followed by the 26 letters A to Z, giving 36 symbols. It is the most compact way to write an integer using only alphanumeric characters, which is why it is popular for short IDs and URL slugs.

Can it handle very large numbers?

Yes. The tool parses input with native BigInt arithmetic, so there is no 32-bit or 64-bit ceiling. You can convert numbers with hundreds of digits without losing precision.

Are negative numbers supported?

Yes. A leading minus sign is preserved across all bases, so -255 displays as -11111111 in binary and -FF in hex. The tool shows sign-and-magnitude form, not two's complement.

Why is my hex input rejected?

Each base only accepts its valid digits. Hex allows 0 to 9 and A to F, so a character like G or a stray space inside the number makes it invalid. Check that every character belongs to the selected base.

Multi-Base Number Display

This tool takes a single integer and shows it at the same time in binary, octal, decimal, hexadecimal, and base-36. Instead of converting one base at a time, you see every common representation in one glance, which is handy when debugging bit masks, color codes, permission flags, or short IDs.

How it works

A positional number system in base b represents a value as a sum of digits multiplied by powers of b. For example the decimal string 255 means 2 * 10^2 + 5 * 10^1 + 5 * 10^0. The tool first parses your input by walking each digit left to right and accumulating acc = acc * b + digit, using BigInt so there is no size limit. Once it has the exact integer value, it re-renders that value in each target base with JavaScript’s toString(radix), which performs repeated division by the new base and reads the remainders.

255 in base 10
 -> binary  11111111
 -> octal   377
 -> hex     FF
 -> base36  73

Tips and notes

You can paste prefixed literals such as 0xFF, 0b1010, or 0o755 and the matching prefix is stripped automatically. Hexadecimal output is shown uppercase by convention, but parsing is case-insensitive. Negative inputs keep their sign in every base. If a character does not belong to the chosen base — for instance the digit 9 while in octal, or G while in hex — the input is flagged as invalid rather than silently producing a wrong answer.