Number Base Converter
Convert numbers between binary, octal, decimal and hexadecimal instantly. Type into any field and the others update live, with support for arbitrarily large integers via BigInt.
About the Number Base Converter
Programmers move between number bases constantly — hexadecimal for colors and memory addresses, binary for flags and bitmasks, decimal for everyday math. Converting by hand is slow and error-prone, especially for large values.
This converter keeps binary, octal, decimal and hex in sync as you edit any one of them, using JavaScript BigInt so even very large integers convert exactly. It runs entirely in your browser.
How to use it
- 1Type a value into the binary, octal, decimal or hex field.
- 2The other bases update instantly.
- 3Copy whichever representation you need.
Features
- Binary, octal, decimal and hexadecimal — all in sync
- Edit any base and the rest update live
- Handles very large integers (BigInt)
- Validates input per base
- One-click copy of any value
Frequently asked questions
How do I convert binary to decimal?
Type your binary number into the binary field and the decimal equivalent (and octal and hex) appears instantly in the other fields.
Does it support large numbers?
Yes. It uses BigInt, so it converts integers far larger than the usual 64-bit limit without losing precision.
What bases are supported?
Binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16) — the four programmers use most.
Is the conversion done locally?
Yes. Everything is computed in your browser; nothing is sent to a server.