Skip to content

Number Base Converter

Computers work internally in binary, and programmers often use hexadecimal notation. Enter an ordinary decimal number to see it instantly in all three systems.

Result

11111111

Binary (base 2)

Octal (base 8)
377
Hexadecimal (base 16)
FF
Decimal (for reference)
255

Formula

Each base expresses the same number using a different number of symbols

Decimal (base 10) uses digits 0-9. Binary (base 2) uses only 0 and 1: each position represents a power of 2. Octal (base 8) uses 0-7, with powers of 8. Hexadecimal (base 16) uses 0-9 and A-F, with powers of 16. The number itself does not change โ€” only the way it is written.

Worked examples

The number 255

โ†’ Binary 11111111, octal 377, hexadecimal FF.

Common mistakes

  • Reading hexadecimal letters (A-F) as separate characters rather than as the values 10 through 15.

When to use it

  • Understanding colour codes, memory sizes and programming assignments given in hex or binary.

Frequently asked questions

Why do programmers use hexadecimal?

Each hexadecimal digit corresponds to exactly 4 binary digits, which makes long binary numbers far more compact and readable.

Was this calculator helpful?