Binary (base 2) is the native language of computers. Each bit is either 0 or 1. To convert binary to decimal, each bit is multiplied by 2 raised to the power of its position (right to left, starting at 0). This tool also shows octal and hexadecimal equivalents.
11001101) into the input field.Binary, decimal, hexadecimal, and octal are four numeral systems representing the same underlying values with different bases: 2, 10, 16, and 8. Programmers and engineers constantly switch between them — reading CPU flags, writing bitmasks, debugging memory dumps, and working with colour codes. This converter handles all four directions simultaneously.
Binary (base-2) is how CPUs actually store data — every register value and memory address is a sequence of 0s and 1s. Hexadecimal (base-16) is a compact shorthand: one hex digit represents exactly 4 binary bits, making hex ideal for reading memory dumps, colour codes (#FF8800), and byte-level flags. Octal (base-8) was common in older Unix file permissions (chmod 755) and still appears in some embedded systems. Decimal is human-readable but the least useful for low-level work.
0x for hex, 0b for binary, 0o for octalWrite the binary number and, starting from the right, multiply each bit by 2 raised to its position: 1101 = (1×8) + (1×4) + (0×2) + (1×1) = 13.
Every hex digit maps to exactly 4 binary bits. The byte value 255 is 11111111 in binary and FF in hex — 2 characters instead of 8. Hex makes binary data much more readable without losing precision.
chmod 755 mean in binary?755 in octal is 111 101 101 in binary — three 3-bit groups for owner, group, and other. Bit pattern 111 = rwx (all permissions), 101 = r-x (read + execute, no write).
The tool uses JavaScript's BigInt for large number support, handling integers well beyond 32-bit and 64-bit ranges without overflow.
See also Hex to Binary, Binary to Text, and the Bitwise Calculator for bit manipulation.