Number Base Converter
Convert whole numbers between binary, octal, decimal and hexadecimal, up to 2^53.
Your details
Result
Decimal
255
- Binary
- 11111111
- Octal
- 377
- Hexadecimal
- FF
Good to know: 255 = 11111111 (binary) = 377 (octal) = FF (hex).
Questions people ask
How do you convert decimal to binary?
Divide by 2 repeatedly and read the remainders backwards: 13 is 1101 binary, because 8 + 4 + 1 = 13.
What is FF in decimal?
255. Each hex digit is 0–15, so FF = 15×16 + 15 = 255, the largest number in one byte.
Why do programmers use hexadecimal?
Each hex digit maps exactly to four binary digits, so it is a compact, readable way to write binary values.
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How we calculate this
We use the standard published formula or definition for this calculation, and we show the working so you can check it.
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