Convert numbers between decimal, binary (base-2), hexadecimal (base-16), and octal (base-8) — with arithmetic operations in each base and bit-level breakdown.
Number Base Converter
ARITHMETIC (optional)
Decimal
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Decimal
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Binary
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Hexadecimal
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Octal
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BIT BREAKDOWN (32-bit)
Enter a number in any base
Converts instantly between decimal, binary, hex, and octal.
Frequently Asked Questions
How do I convert decimal to binary?
Repeatedly divide the number by 2, recording the remainder each time. Read the remainders bottom-to-top. Example: 13 ÷ 2 = 6 R1, 6 ÷ 2 = 3 R0, 3 ÷ 2 = 1 R1, 1 ÷ 2 = 0 R1 → binary = 1101.
What is hexadecimal used for?
Hex (base-16) uses digits 0–9 and letters A–F. It is used widely in computing because it maps neatly to binary (each hex digit = 4 bits). Color codes in CSS (#FF6600), memory addresses, and bytecodes are expressed in hex.