Hex to Decimal Converter
Paste a hexadecimal value to get its decimal number instantly. A 0x prefix, spaces and any letter case are all fine, and big values stay exact. Everything runs in your browser.
How to convert hex to decimal
- Paste or type your hex value. A leading 0x is optional.
- Read the decimal result, which updates as you type.
- Copy the decimal number with one click.
Examples
Common byte value
0xFF
255
32-bit word
deadbeef
3735928559
Frequently asked questions
How does hex to decimal conversion work?
Each hex digit is a power of 16. Reading right to left, the digits are worth 1, 16, 256 and so on, and the weighted digits are added together. For example 0xFF is 15 times 16 plus 15, which is 255.
What does the 0x prefix mean?
0x is a common marker that labels a number as hexadecimal, used in many programming languages. It is not part of the value, so this converter accepts it but ignores it. FF and 0xFF give the same result.
Does letter case matter?
No. Hex digits A through F are case-insensitive, so ff, FF and Ff all convert to 255. You can paste values in any case.
Can it handle very large hex numbers?
Yes. The conversion uses BigInt for arbitrary precision, so even values far beyond 64 bits convert exactly with no rounding or loss.
What happens if my input is not valid hex?
If the value contains anything other than the digits 0 to 9 and the letters A to F, you get an Invalid hexadecimal message. Spaces and a single 0x prefix are allowed and stripped automatically.
Is my data uploaded anywhere?
No. The conversion runs entirely in your browser, so your hex value never leaves your device.
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