Number Base Converter
Convert numbers between binary, octal, decimal, and hexadecimal instantly. Enter any number in any base and see all four representations at once.
Click any value to copy it.
What is Number Base Conversion?
Number base conversion (also called radix conversion) transforms a number from one positional numeral system to another. The four most common bases in computing are binary (base 2), octal (base 8), decimal (base 10), and hexadecimal (base 16).
When Each Base is Used
- Binary (base 2) — used internally by all digital computers; only digits 0 and 1.
- Octal (base 8) — used in Unix/Linux file permissions (e.g.
chmod 755). - Decimal (base 10) — the everyday number system humans use.
- Hexadecimal (base 16) — used in memory addresses, color codes (
#FF5733), and byte representation. Uses digits 0–9 and A–F.
Frequently Asked Questions
What is the maximum number this tool supports?
This tool uses JavaScript's 32-bit integer parsing, which supports values up to 2,147,483,647 (decimal) or 7FFFFFFF (hex). For larger numbers, a specialized big-integer library would be required.
How do I convert a hexadecimal color to RGB?
Take each pair of hex digits and convert them to decimal. For example, #FF5733: FF = 255, 57 = 87, 33 = 51 → RGB(255, 87, 51). Use our Color Converter tool for an easier workflow.