Free Online Binary to Decimal Converter

How to convert binary to decimal

Convert binary numbers to decimal instantly: type a value and the decimal result appears as you type. Below the converter you'll find the method to do it by hand, a worked example and a table of common values.

1. Type or paste a binary number into the box above. Negative numbers and fractions work too.
2. The From and To bases are already set to binary and decimal, so the result appears right away: 10011100 becomes 156.
3. Copy the result, or choose any other base from 2 to 60 to convert the same value.

Converting binary to decimal by hand

Number the digits from right to left, starting at 0. Multiply each digit by 2 to the power of its position and add the results together:

10011100₂ = 1·2⁷ + 0·2⁶ + 0·2⁵ + 1·2⁴ + 1·2³ + 1·2² + 0·2¹ + 0·2⁰
= 128 + 0 + 0 + 16 + 8 + 4 + 0 + 0 = 156₁₀

Binary to decimal table

Binary and decimal explained

Binary is base 2: it uses only the digits 0 and 1, and each position is worth twice the one to its right. It is how computers store every number, character and pixel.

Decimal is base 10, the everyday number system with the digits 0 to 9. Each position is worth ten times the one to its right.