# Binary to Decimal Converter

> Convert binary numbers to decimal, hex and octal instantly.

To convert binary to decimal, enter a string of ones and zeros above. Each digit is weighted by its power of two and summed, and the tool also shows the same value in octal and hexadecimal for comparison.

**URL:** https://convertto.tech/t/binary-to-decimal
**Category:** Number Tools (https://convertto.tech/c/number-tools)
**Privacy:** Runs entirely in the browser; no upload
**Cost:** Free, no sign-up
**Last updated:** 2026-08-01

## Key facts

- **Privacy:** Runs entirely in your browser — nothing is uploaded
- **Cost:** Free, unlimited, no sign-up

## How to use

1. Enter or paste your value.
2. The result appears immediately — copy or download it.

## FAQ

### How do I convert binary to decimal by hand?

Multiply each digit by two raised to its position, counting from zero on the right, then add the results. So 1011 is 8 + 0 + 2 + 1 = 11. The doubling method is faster in practice: start at the left, double the running total and add the next digit.

### Why does binary matter if computers hide it?

It surfaces whenever a value overflows, a bitmask is used for permissions, or a colour is packed into an integer. A file permission of 755 is three sets of three bits — read, write, execute — which only makes sense in binary.

### What is the largest number a given number of bits holds?

Two to the power of the bit count, minus one. Eight bits reach 255, sixteen reach 65,535, and thirty-two reach 4,294,967,295 — which is why unsigned 32-bit counters wrap at roughly 4.3 billion.

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