How do I convert decimal to binary?

Divide the decimal number by 2 repeatedly, recording the remainder each time. Read the remainders from bottom to top. For example, 13 in binary: 13÷2=6r1, 6÷2=3r0, 3÷2=1r1, 1÷2=0r1 → 1101.

What is hexadecimal used for?

Hexadecimal is used in programming for colour codes (#FF5733), memory addresses, MAC addresses, and representing binary data compactly. Each hex digit represents exactly 4 binary digits.

Why do computers use binary?

Computers use binary because electronic circuits have two states: on (1) and off (0). This makes binary the natural language of digital hardware.

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Free Number Base Converter — Decimal, Binary, Hex, Octal

Convert between decimal, binary, octal, and hexadecimal

Decimal (Base 10)

Binary (Base 2)

Octal (Base 8)

Hexadecimal (Base 16)

Quick Reference

Dec	Bin	Oct	Hex
0	0	0	0
1	1	1	1
2	10	2	2
4	100	4	4
8	1000	10	8
10	1010	12	A
15	1111	17	F
16	10000	20	10
255	11111111	377	FF
256	100000000	400	100

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About Number Base Conversion

Number bases (or radixes) are systems for representing numbers. Decimal (base 10) is everyday counting. Binary (base 2) is the foundation of computing — every digital device operates in binary. Hexadecimal (base 16) is a compact way to represent binary data, widely used in programming, colour codes, and memory addresses. Octal (base 8) was historically used in computing.

This converter handles binary, octal, decimal, and hexadecimal conversions instantly. Perfect for programmers, students, and anyone working with different number systems.

Quick Reference

Decimal 10 = Binary 1010 = Hex A = Octal 12
Decimal 255 = Binary 11111111 = Hex FF = Octal 377
Decimal 16 = Binary 10000 = Hex 10 = Octal 20