Convert Binary to Decimal

Convert binary numbers to decimal instantly. Learn binary-to-decimal conversion with step-by-step math. Free online tool.

Input
Number
From Base
2-36
Results
2
Binary
Base 2
0b11111111
8
Octal
Base 8
0o377
10
Decimal
Base 10
255
16
Hexadecimal
Base 16
0xFF
Step-by-Step Conversion
Step 1: Convert Decimal 255 to Binary
255 / 2 = 127 remainder 1
127 / 2 = 63 remainder 1
63 / 2 = 31 remainder 1
31 / 2 = 15 remainder 1
15 / 2 = 7 remainder 1
7 / 2 = 3 remainder 1
3 / 2 = 1 remainder 1
1 / 2 = 0 remainder 1
Result: 11111111

About This Conversion

Binary (base-2) is the fundamental number system used by all digital computers. Every piece of data in a computer is stored as a sequence of 0s and 1s. Converting binary to decimal involves multiplying each bit by its positional power of 2 and summing the results. For example, binary 1010 = (1x8) + (0x4) + (1x2) + (0x1) = 10 in decimal. This conversion is essential for computer science students, network engineers working with IP addresses and subnet masks, and embedded systems programmers who work directly with binary registers and flags.

Frequently Asked Questions

How do I convert binary to decimal?
Starting from the rightmost bit, multiply each bit by 2 raised to its position (starting from 0). Then sum all values. Example: 1101 = (1x8) + (1x4) + (0x2) + (1x1) = 13.
What is binary 11111111 in decimal?
Binary 11111111 = 255 in decimal. This is the maximum value for an 8-bit (1 byte) unsigned integer.

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