Binary, octal, decimal and hex converter
Enter a number in any base and see it in binary, octal, decimal and hexadecimal at once.
Fill in the form — the result appears here instantly
How it works: Number base converter
Choose the base of the number you type and see every base at once. Prefixes such as 0b and 0x are fine, and BigInt maths keeps very long numbers exact.
Hexadecimal uses 0–9 and A–F for 10–15, so FF = 255 — common in colour codes (#FF0000) and memory addresses.
FAQ
What is 255 in binary?
11111111 — eight bits all set to 1.
Can it convert fractions?
No, this page converts positive whole numbers.
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