Convert between binary, octal, decimal and hexadecimal online. Enter the value and get the result in the desired base. Free.
Number bases are systems for representing quantities using different sets of digits. Decimal (base 10) uses digits 0 to 9 and is the system we use every day. Binary (base 2) uses only 0 and 1, and is the native language of computers — each binary digit is a bit. Octal (base 8) uses 0 to 7, and hexadecimal (base 16) uses 0 to 9 and the letters A to F, widely used in programming and memory addressing. Conversion between bases works by converting the source-base value to an integer and then representing that number in the target base. For example, binary 1010 equals decimal 10 and hexadecimal A. Hexadecimal FF equals decimal 255 and binary 11111111. This converter accepts text input (e.g., 1010 in binary, FF in hexadecimal, 377 in octal) and validates the digits according to the source base — if you type "2" in binary, the result will be empty, since 2 is not a valid digit in base 2. It is essential for computer science students, programmers, electronics engineers, and anyone working with digital systems, network addressing, or low-level debugging.
Sum the digits multiplied by powers of 2. E.g., 1010 = 1×8 + 0×4 + 1×2 + 0×1 = 10.
Divide the number by 16 repeatedly and read the remainders bottom-up. E.g., 255 = FF.
16 digits: 0–9 and A–F, where A=10, B=11, C=12, D=13, E=14, F=15.
Because the entered value contains invalid digits for the source base (e.g., "2" in binary). Check the digits and try again.
Yes, completely free, with no registration and no usage limit.