Binary to Decimal Converter

Convert binary numbers to decimal, hexadecimal, and octal. Supports any binary input. Ideal for students and programmers.

Decimal
Hexadecimal
Octal

How to Use This Calculator

  1. Enter a binary number (only 0s and 1s, e.g. 1010).
  2. The decimal, hexadecimal, and octal equivalents appear immediately.
  3. No spaces or prefixes needed — just the binary digits.

Formula

Decimal = sum of (bit × 2^position), reading from right (position 0).

1010 = (1×2³) + (0×2²) + (1×2¹) + (0×2⁰) = 8 + 0 + 2 + 0 = 10

Example

Example: Convert 11001100 to decimal:

128 + 64 + 0 + 0 + 8 + 4 + 0 + 0 = 204

Frequently Asked Questions

  • Binary is a base-2 number system using only 0 and 1. It is the fundamental language of all digital computers and electronics.
  • Multiply each bit by 2 raised to its position (from right, starting at 0), then sum all values. For example, 1010 = 1×8 + 0×4 + 1×2 + 0×1 = 10.
  • Eight bits (e.g. 11001100) form one byte. A byte can represent values from 0 to 255.
  • 11111111 in binary = 255 in decimal. This is the maximum value for one byte (8 bits).
  • Each hex digit maps exactly to 4 binary bits. For example, F (hex) = 1111 (binary), so FF = 11111111.

Related Calculators