Free Online Number Base Converter

Convert between binary, octal, decimal, and hexadecimal. Type in any field and all others update live.

Binary (Base 2)
Octal (Base 8)
Decimal (Base 10)
Hexadecimal (Base 16)
Custom Base (2-36)
Base

How to Use This Number Base Converter

Type a number in any field and all other bases update live. Supports binary (base 2), octal (base 8), decimal (base 10), hexadecimal (base 16), and any custom base from 2 to 36.

What bases are supported?

Binary (2), octal (8), decimal (10), hexadecimal (16), and any custom base from 2 to 36.

Can it handle large numbers?

JavaScript safely handles integers up to 2^53 - 1 (about 9 quadrillion). Numbers larger than this may lose precision.

What characters are used for bases above 10?

Letters A-Z represent values 10-35. For hexadecimal, A=10, B=11, C=12, D=13, E=14, F=15.

Is my data stored?

No. All conversion runs locally in your browser.