Enter a number and its base to see it in binary, octal, decimal and hexadecimal.
Each digit is multiplied by the base raised to its position: 101101₂ = 1×32 + 0×16 + 1×8 + 1×4 + 0×2 + 1×1.
45 in decimal = 101101 in binary (32 + 8 + 4 + 1) = 2D in hexadecimal (2 × 16 + 13).