Convert Hexadecimal to Decimal
Enter a Hexadecimal number to get its Decimal value — plus every other common base. Exact even for huge integers, all in your browser.
That's not a valid number for the selected base.
- Binary base 2
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- Octal base 8
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- Decimal base 10
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- Hexadecimal base 16
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Worked example
ff in Hexadecimal converts to 255 in Decimal. The converter above is pre-filled with this value — edit it to see the result update live.
Hexadecimal to Decimal reference table
| Decimal | Hexadecimal | Decimal |
|---|---|---|
| 10 | a | 10 |
| 16 | 10 | 16 |
| 32 | 20 | 32 |
| 100 | 64 | 100 |
| 255 | ff | 255 |
Common uses
Essential for translating computer-friendly hex codes back into human-readable numbers for analysis or calculation.
Related conversions
Need another base? The full number base converter handles any base from 2 to 36 and converts them all simultaneously.
Frequently asked questions
How do I convert Hexadecimal to Decimal?
Enter your Hexadecimal value into the converter above and it shows the Decimal equivalent — along with every other base — instantly. For example, ff in Hexadecimal becomes 255 in Decimal.
Can it handle very large numbers?
Yes. The converter uses arbitrary-precision math, so even numbers with hundreds of digits convert exactly without the rounding errors you'd get from a normal calculator.
Is my data sent to a server?
No. Every conversion runs locally in your browser using standard JavaScript BigInt math, so nothing you enter is uploaded.