Binary to Decimal Converter

About Binary to Decimal Converter

A number base, or radix, is the count of distinct digits a positional numeral system uses: 2 for binary, 8 for octal, 10 for decimal, 16 for hexadecimal. This tool reads your input digit by digit into a BigInt, so integers of any length convert exactly, then prints the value in bases 2, 8, 10, 16, and 36. It handles whole numbers only, not fractions. Spaces, underscores, and a leading 0x or 0b are ignored.

Also known as: Binary to Hex Converter.

How to use Binary to Decimal Converter

1. Fill in "Number" and "From base".
2. The result appears below and updates as you type.
3. Copy the result with the copy button, or download it as a file where that is offered.

Questions about Binary to Decimal Converter

How do you convert binary to decimal by hand?

Multiply each bit by its power of two, counting from zero at the right, and add the results. For 1011 that is 8 + 0 + 2 + 1 = 11. The tool does the same with exact integer arithmetic.

Why is hexadecimal used so often in computing?

One hex digit maps to exactly four bits, so a byte is always two hex digits. That makes memory addresses, color codes, and raw bytes much shorter to write than binary while staying easy to convert.