Binary to Decimal Converter

Free online tool to convert between binary and decimal numbers instantly. Perfect for students, programmers, and anyone learning about number systems.

Binary to Decimal

Decimal Result:
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Decimal to Binary

Binary Result:
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How Binary to Decimal Conversion Works

Converting binary to decimal is all about understanding position values. Each digit in a binary number represents a power of 2, starting from the right:

  • Rightmost position: 2⁰ = 1
  • Second position: 2¹ = 2
  • Third position: 2² = 4
  • Fourth position: 2³ = 8
  • And so on, doubling each time...

Example: Converting 1011 to Decimal

1 0 1 1

Reading from right to left:

  • 1 × 2⁰ = 1 × 1 = 1
  • 1 × 2¹ = 1 × 2 = 2
  • 0 × 2² = 0 × 4 = 0
  • 1 × 2³ = 1 × 8 = 8

Sum: 8 + 0 + 2 + 1 = 11

Result: 1011₂ = 11₁₀

How Decimal to Binary Conversion Works

To convert decimal to binary, we use the "division by 2" method:

  1. Divide the number by 2
  2. Write down the remainder (0 or 1)
  3. Divide the quotient by 2 again
  4. Repeat until the quotient is 0
  5. Read the remainders from bottom to top

Example: Converting 13 to Binary

13 ÷ 2 = 6remainder 1
6 ÷ 2 = 3remainder 0
3 ÷ 2 = 1remainder 1
1 ÷ 2 = 0remainder 1

Reading remainders from bottom to top:

Result: 13₁₀ = 1101₂

Common Binary-Decimal Conversions

Here are some frequently used conversions to memorize:

DecimalBinary
00
11
101010
151111
1610000
32100000
641000000
1001100100
12810000000
25511111111

Why Binary Conversion Matters

For Programmers

  • Understanding bitwise operations
  • Working with binary flags and permissions
  • Network programming (IP addresses, subnet masks)
  • Debugging at the bit level

For Students

  • Computer science fundamentals
  • Digital logic and circuits
  • Computer architecture courses
  • Understanding how computers store data

In Real Life

  • RGB color codes (0-255 for each channel)
  • File sizes (kilobytes, megabytes based on powers of 2)
  • Understanding computer memory (RAM sizes: 4GB, 8GB, 16GB...)
  • Appreciating the digital world around you

Learn More About Binary

Want to deepen your understanding of binary? Check out these resources: