Number Base Converter
Convert integers between binary, octal, decimal, hex and any base from 2 to 36.
What is a number base?
The base, or radix, is how many distinct digits a numbering system uses. Decimal is base 10 (digits
0-9); computers lean on binary (base 2), octal (base 8) and
hexadecimal (base 16, using a-f). The same quantity — say 255 — is written
11111111 in binary and FF in hex.
Converting between any bases
Pick a source and target base anywhere from 2 to 36. The tool first checks that every digit is legal for the source base, converts to a plain integer, and then renders it in the target base. Values beyond about 9 quadrillion may lose precision, since the conversion uses JavaScript's native number type.
How to use the Number Base Converter
- Enter a value. Type the number using digits valid for its base.
- Choose the from base. Tell the tool how to read your input (2 to 36).
- Choose the to base. Pick the base you want the result in.
- Read the result. See the converted value and its decimal equivalent.
Frequently asked questions
Which bases are supported?
Any base from 2 to 36. Above 10, letters a-z act as the extra digits, matching JavaScript's parseInt and toString.
Why is my input rejected?
Every digit must be valid for the chosen source base. For example the letter F is only allowed in base 16 or higher, not in decimal.
Can it handle huge numbers?
Very large values may lose precision because the conversion uses the native number type. Keep integers below roughly 2^53 for exact results.
Does it convert fractions?
No. This tool converts whole integers between bases; decimal points are not supported.