Number Base Converter
How to Convert Binary to Decimal
Binary uses only 0s and 1s, where each position is a power of two. Converting to decimal means adding up the place values. The tool below does it instantly, and here's the method.
Convert binary to decimal
Octal (8)
12
Decimal (10)
10
Hex (16)
a
The method
- Write the place values from right to left: 1, 2, 4, 8, 16, …
- For each binary digit that's a 1, take its place value.
- Add those place values together to get the decimal number.
Worked example: 1010
From the right, the digits are 0, 1, 0, 1 with place values 1, 2, 4, 8. The 1s are in the 2 and 8 positions.
So 1010 in binary = 8 + 2 = 10 in decimal.
Frequently asked questions
How do you convert binary to decimal?
Add up the place values (1, 2, 4, 8, …) for each position that holds a 1. For 1010 that's 8 + 2 = 10.
What is 1111 in decimal?
1 + 2 + 4 + 8 = 15.
Can the tool convert other bases too?
Yes — the converter above also handles octal and hexadecimal alongside binary and decimal.