Common Number Representations
Different number bases are used in various computing contexts:
- Binary (Base 2) is used in digital circuits and low-level computing
- Octal (Base 8) is used in some Unix file permissions
- Decimal (Base 10) is our standard counting system
- Hexadecimal (Base 16) is used for memory addresses, colors, and more
About the Base Converter
A base (radix) converter changes a number between numeral systems — binary (base 2), octal (base 8), decimal (base 10) and hexadecimal (base 16). Programmers hop between these constantly: hex for colours and memory, binary for bit flags, decimal for humans.
Enter a number in any base and see it in the others instantly, in your browser. It saves you the error-prone manual conversion and handy for debugging, low-level programming, and learning how number systems work.
How to use the Base Converter
- 1Enter a number and select its current base.
- 2Read the equivalent value in binary, octal, decimal and hex.
- 3Copy the representation you need.
Common uses
Programming
Convert between hex, decimal and binary while debugging or working with bitmasks.
Colour & memory values
Read a hex colour or address as decimal, or vice versa.
Learning number systems
See how the same value looks across bases.
Frequently asked questions
Why do programmers use hexadecimal?
Hex maps neatly to binary — each hex digit is exactly 4 bits — so it's a compact, readable way to write binary values like colours and memory addresses.
What do the letters in hex mean?
Hex digits go 0–9 then A–F, where A=10 up to F=15, because base 16 needs sixteen distinct symbols.
Can it convert fractions or negatives?
It focuses on non-negative integers, which covers the vast majority of base-conversion needs in programming.
Is my input sent anywhere?
No. Conversion is done locally in your browser.