Number Base Converter — Binary, Hex, Octal, Decimal
Convert numbers between binary, octal, decimal, and hexadecimal.
How to Use Number Base Converter
Select the input base (binary, octal, decimal, hex)
Enter a number
See the value in all four bases instantly
Your files never leave your browser
No upload wait time. Results in seconds
No daily limits, no file count limits
No account, no subscription, no fees
About Number Systems
Different number bases are used for different purposes in computing. Decimal (base 10) is human-friendly, binary (base 2) is what hardware uses, hexadecimal (base 16) is compact for memory addresses and colors, and octal (base 8) appears in Unix file permissions.
Quick Reference
- 255 decimal =
FFhex =11111111binary - Color codes: #FF4500 = rgb(255, 69, 0)
- Permissions: chmod 755 = rwxr-xr-x
Frequently Asked Questions
What number bases are supported?
Binary (base 2), Octal (base 8), Decimal (base 10), and Hexadecimal (base 16) — the four most common bases in programming.
What is the maximum number?
JavaScript safely handles integers up to 2^53 − 1 (9,007,199,254,740,991). Larger values may lose precision.