Binary, Decimal & Hexadecimal Converter (Free, with Steps)

Use this free number base converter to move a whole number between binary, decimal, hexadecimal and octal. Enter a value, pick the base it’s written in, and you’ll get all four forms together with the steps — positional expansion to decimal, then repeated division into the target base.

How to use the converter

1. Enter a non-negative whole number.
2. Choose which base it is currently written in.
3. Read the value in binary, decimal, hexadecimal and octal, with the working shown.

How base conversion works

To go to decimal, multiply each digit by its place value (a power of the base) and add. To go from decimal to another base, divide repeatedly by the new base and read the remainders from bottom to top. Binary uses digits 0–1, hexadecimal uses 0–9 and A–F.

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Frequently asked questions

How do you convert decimal to binary?

Divide the number by 2 repeatedly, writing down each remainder, then read the remainders bottom-to-top. 156 becomes 10011100.

What does hexadecimal A–F mean?

Hex digits go beyond 9 using letters: A = 10, B = 11, C = 12, D = 13, E = 14, F = 15. So decimal 156 is 9C in hex.

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Can it convert octal too?

Yes — it shows binary, decimal, hexadecimal and octal all at once, whichever base you start from.

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Read the full lesson: learn the method step by step.

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