Binary to Decimal Converter

Convert any binary number to decimal (base-10), octal and hexadecimal — with the positional value method shown step by step.

What Does This Tool Do?

Convert binary numbers to decimal, octal and hexadecimal. Shows the positional value method — each bit multiplied by its power of 2 — so you can learn and verify the conversion.

Key Features

🔢
3 Outputs
Decimal, octal and hex from one binary input.
📐
Positional Steps
Each bit × 2^n shown clearly.
Live
Updates as you type.
Validates Input
Warns if non-binary characters are entered.

How to Use

  1. Type or paste a binary number (0s and 1s only).
  2. Decimal, octal and hex appear instantly.
  3. Read the positional value steps to learn the method.

Frequently Asked Questions

How do you convert binary to decimal?
Multiply each bit by 2 raised to its position (from right, starting at 0), then sum all values. E.g. 1101 = 1×8 + 1×4 + 0×2 + 1×1 = 13.
What is the largest binary number this handles?
JavaScript integers are safe up to 2^53 − 1, so binary strings up to 53 bits convert accurately.
How do I convert binary to hex?
Group binary digits in sets of 4 from the right, then convert each group to its hex digit. This tool does it automatically.