Convert numbers between bases

How it works

1. 1

   Type a number into the field for its base.

2. 2

   Read the result in the other three bases.

About the Number Base Converter (Bin/Hex)

Programmers move between number bases constantly: hexadecimal for colours and memory addresses, binary for bit flags, octal for Unix permissions. This converter shows one value in binary, octal, decimal and hexadecimal at once, and updates the other three when you edit any of them. It uses arbitrary-precision integers, so very large numbers convert exactly.

What you can do

• Convert between base 2, base 8, base 10 and base 16.
• Edit any of the four fields to update the rest.
• Work with integers of any size without rounding, such as 64-bit IDs or hashes.
• Type hex digits in upper or lower case; output is lower case.

When it works best

• Reading bit flags or a register value as binary.
• Converting a hex error code or memory address to decimal for a log search.
• Checking chmod values like 755 against their binary permission bits.

Things to know

• Everything runs in your browser.
• Only non-negative whole numbers are accepted. Minus signs, fractions and spaces are rejected.
• Prefixes such as 0x, 0b and 0o are not stripped automatically, so leave them out.
• To see the bytes of text rather than a number, use Text to Binary/Hex. For permissions, the Chmod Permission Calculator is quicker.

Frequently asked questions