HexCalculator
Hex to decimal converter (and decimal to hex)
Type a number in either field and the other converts as you type — hex to decimal
or decimal to hex. The breakdown below shows the actual math for your number,
not a canned example. Prefixes like 0x, spaces and underscores are fine.
Same number in every base
Step by step
Type a number above to see the conversion worked out step by step.
How hex to decimal conversion works
Hexadecimal is base 16: each digit position is worth a power of 16, and the letters A–F stand for the values 10–15. To convert to decimal, multiply each digit by its positional value and add everything up:
1A3₁₆ = 1×16² + A(10)×16¹ + 3×16⁰ = 256 + 160 + 3 = 419₁₀
Going the other way — decimal to hex — divide repeatedly by 16 and read the remainders from bottom to top. The converter above shows both directions on whatever number you give it.
Hex digit reference
| Hex | Decimal | Binary |
|---|---|---|
| 0 | 0 | 0000 |
| 1 | 1 | 0001 |
| 2 | 2 | 0010 |
| 3 | 3 | 0011 |
| 4 | 4 | 0100 |
| 5 | 5 | 0101 |
| 6 | 6 | 0110 |
| 7 | 7 | 0111 |
| 8 | 8 | 1000 |
| 9 | 9 | 1001 |
| A | 10 | 1010 |
| B | 11 | 1011 |
| C | 12 | 1100 |
| D | 13 | 1101 |
| E | 14 | 1110 |
| F | 15 | 1111 |
Common hex values
Powers of two and "all ones" masks come up constantly. These are the ones worth recognizing on sight:
| Hex | Decimal | Binary |
|---|---|---|
| 0x7F | 127 | 0111 1111 |
| 0x80 | 128 | 1000 0000 |
| 0xFF | 255 | 1111 1111 |
| 0x100 | 256 | 0001 0000 0000 |
| 0x3FF | 1 023 | 0011 1111 1111 |
| 0x400 | 1 024 | 0100 0000 0000 |
| 0xFFF | 4 095 | 1111 1111 1111 |
| 0x1000 | 4 096 | 0001 0000 0000 0000 |
| 0x7FFF | 32 767 | 0111 1111 1111 1111 |
| 0xFFFF | 65 535 | 1111 1111 1111 1111 |
| 0x10000 | 65 536 | 0001 0000 0000 0000 0000 |
| 0x7FFFFFFF | 2 147 483 647 | 0111 1111 1111 1111 1111 1111 1111 1111 |
| 0xFFFFFFFF | 4 294 967 295 | 1111 1111 1111 1111 1111 1111 1111 1111 |
Where you'll meet hex numbers
Memory addresses (0x7FFF5FBFF8C0), color codes (#FFA700),
byte dumps, permission masks, MAC addresses, error codes — hexadecimal shows up
anywhere data is described byte by byte, because two hex digits are exactly one byte.
Related tools and guides
- How to convert hex to decimal by hand — the method, with worked examples.
- Hex ↔ binary converter — each hex digit is exactly four bits.
- Hex calculator — add, subtract, multiply, divide and bitwise-operate in hex.
- Hex table 0x00–0xFF — every byte value in decimal, binary and octal.
- Octal ↔ decimal converter — the same method in base 8.