Binary Converter
Convert numbers between binary, decimal, hexadecimal, and octal.
This tool is for informational and educational purposes only. It is not a substitute for professional financial, medical, legal, or engineering advice. See Terms of Service.
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Request a ToolHow to Use the Binary Converter
Select the base of your input number, type the value, and all conversions appear instantly.
- Choose the input base. Select whether your number is decimal (base 10), binary (base 2), or hexadecimal (base 16).
- Enter the value. Type the number in the selected base. For binary, use only 0 and 1. For hex, use 0-9 and A-F.
- Read the conversions. The decimal value is shown prominently, and a table below displays the number in all four bases: decimal, binary, hex, and octal.
About Number Base Conversion
Computers work in binary (base 2), using only the digits 0 and 1. Humans typically use decimal (base 10). Hexadecimal (base 16) is a compact way to represent binary data, since each hex digit maps to exactly 4 binary digits. Octal (base 8) maps each digit to 3 binary digits.
To convert from any base to decimal, multiply each digit by the base raised to its position power and sum the results. This calculator handles the conversion automatically in both directions.
Frequently Asked Questions
How do I convert binary to decimal?
Multiply each binary digit by 2 raised to its position (starting from 0 on the right). For example, 1010 in binary = 1x8 + 0x4 + 1x2 + 0x1 = 10 in decimal.
What is hexadecimal?
Hexadecimal is base 16, using digits 0-9 and letters A-F (where A=10, B=11, C=12, D=13, E=14, F=15). It is commonly used in programming to represent colors, memory addresses, and binary data compactly.
Why do computers use binary?
Computers use binary because their circuits have two states: on and off (1 and 0). This makes binary the natural number system for digital electronics. All data in a computer is stored and processed as binary.