Binary to Decimal Calculator

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Binary to Decimal Calculator

Convert any base-2 binary number into its decimal (base-10) equivalent instantly. Free, accurate, and includes a full step-by-step breakdown of the calculation.

Instant Results
📐 Step-by-Step Breakdown
🎓 Educational
📱 Mobile Friendly

Convert Binary to Decimal

Enter a binary number below using only 0s and 1s. Your decimal equivalent updates instantly, along with a full positional breakdown showing exactly how each digit contributes to the final value.

Enter Your Binary Number

Only digits 0 and 1 are valid

🔢 Binary Input
Use only 0s and 1s. Up to 53 digits are supported.
💡 Tip: Try well-known values like 1111 (15), 11111111 (255), or 10000000 (128) to see the conversion in action.

Conversion Result

Your binary number in decimal form

How Binary to Decimal Conversion Works

Every binary digit, or “bit,” represents a power of 2 based on its position, counting from the right starting at zero. Here is the three-step process behind every calculation this tool performs.

01

Assign Place Values

Starting from the rightmost digit, assign each bit a power of 2: 2⁰, 2¹, 2², and so on, moving left.

02

Multiply Each Digit

Multiply every bit (0 or 1) by its corresponding power of 2. A 0 contributes nothing; a 1 contributes the full value of that position.

03

Sum the Results

Add together every non-zero product from step two. The total is the decimal equivalent of your binary number.

Common Binary to Decimal Values

Standard binary-to-decimal equivalents for the numbers 0 through 15, useful for quickly checking your own calculations.

Binary Decimal
00000
00011
00102
00113
01004
01015
01106
01117
10008
10019
101010
101111
110012
110113
111014
111115
⚠️ Important Note: This calculator interprets input as an unsigned binary number. It does not apply two’s complement, so it will not return negative decimal values.

Binary to Decimal FAQ

Everything you need to know about converting binary numbers to decimal.

Multiply each binary digit by 2 raised to the power of its position, counting from 0 on the right, then add the results together. For example, binary 101 is (1×2²) + (0×2¹) + (1×2⁰) = 4 + 0 + 1 = 5.

Binary 1010 equals decimal 10. It is calculated as (1×2³) + (0×2²) + (1×2¹) + (0×2⁰) = 8 + 0 + 2 + 0 = 10.

Binary is a base-2 numeral system, so it only has two possible digits: 0 and 1. Computers use it because digital circuits naturally represent two states, such as off and on or low and high voltage.

This calculator safely handles binary numbers up to 53 bits long, which covers virtually all everyday, academic, and programming use cases without losing precision.

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