If you work with programming, networking, or digital electronics, you run into hexadecimal numbers all the time. This tool helps you quickly convert a hex value (base-16) into decimal (base-10), with support for very large values using accurate integer math.
What is hexadecimal?
Hexadecimal is a number system with 16 symbols:
- 0–9 represent values 0 through 9
- A–F represent values 10 through 15
Because one hex digit maps neatly to 4 binary bits, hexadecimal is widely used as a compact way to display binary data.
How hex to decimal conversion works
Decimal uses powers of 10. Hexadecimal uses powers of 16. To convert, multiply each hex digit by its place value and add the results.
Formula
Decimal = dn×16n + dn-1×16n-1 + ... + d0×160
Example: Convert 2F7
- 2 × 162 = 2 × 256 = 512
- F (15) × 161 = 15 × 16 = 240
- 7 × 160 = 7 × 1 = 7
- Total = 512 + 240 + 7 = 759
Common hex digit values
| Hex Digit | Decimal Value |
|---|---|
| 0 | 0 |
| 1 | 1 |
| 2 | 2 |
| 3 | 3 |
| 4 | 4 |
| 5 | 5 |
| 6 | 6 |
| 7 | 7 |
| 8 | 8 |
| 9 | 9 |
| A | 10 |
| B | 11 |
| C | 12 |
| D | 13 |
| E | 14 |
| F | 15 |
Where this conversion is useful
- Web development: color values like
#FFAA33 - Systems programming: memory addresses and machine-level data
- Networking: IPv6 chunks and protocol fields
- Cybersecurity: packet inspection and hash representations
- Embedded devices: registers and hardware-level debugging
Tips to avoid mistakes
- Don’t treat A–F as letters; they are numbers 10–15.
- Watch place values carefully from right to left.
- Ignore case:
afandAFare equal. - A leading
0xis notation only; it does not change the value.
Quick FAQ
Can this calculator convert very large hex numbers?
Yes. It uses JavaScript BigInt arithmetic, so it can handle values far beyond normal integer limits.
Does it accept negative hexadecimal values?
Yes. You can enter values like -FF or -0x1A.
Is uppercase required?
No. Both uppercase and lowercase are accepted.