Explained with a place-value breakdown — reference tables, charts, and a live converter.
255 in hexadecimal is ff (0xff).
1. Divide by the base repeatedly
Divide 255 by 16 again and again, noting the remainder each time:
2. Collect the remainders
255 ÷ 16 = 15, remainder f · 15 ÷ 16 = 0, remainder f
3. Read the remainders bottom to top
Reading the remainders from bottom to top gives ff — that is 255 in hexadecimal.
Each digit of ff is multiplied by its place value (a power of 16); the sum is 255 (in decimal).
| Digit | Place value | Contribution |
|---|---|---|
| F | 161 = 16 | 15 × 16 = 240 |
| F | 160 = 1 | 15 × 1 = 15 |
| Sum | 255 |
| Number base | Representation | With prefix |
|---|---|---|
| Binary | 11111111 | 0b11111111 |
| Octal | 377 | 0o377 |
| Decimal | 255 | — |
| Hexadecimal | FF | 0xFF |
| Decimal | Binary | Octal | Hexadecimal |
|---|---|---|---|
| 0 | 0 | 0 | 0 |
| 1 | 1 | 1 | 1 |
| 2 | 10 | 2 | 2 |
| 3 | 11 | 3 | 3 |
| 4 | 100 | 4 | 4 |
| 5 | 101 | 5 | 5 |
| 6 | 110 | 6 | 6 |
| 7 | 111 | 7 | 7 |
| 8 | 1000 | 10 | 8 |
| 9 | 1001 | 11 | 9 |
| 10 | 1010 | 12 | A |
| 11 | 1011 | 13 | B |
| 12 | 1100 | 14 | C |
| 13 | 1101 | 15 | D |
| 14 | 1110 | 16 | E |
| 15 | 1111 | 17 | F |
| 16 | 10000 | 20 | 10 |
| 32 | 100000 | 40 | 20 |
| 64 | 1000000 | 100 | 40 |
| 128 | 10000000 | 200 | 80 |
| 255 | 11111111 | 377 | FF |
| 256 | 100000000 | 400 | 100 |
| 1024 | 10000000000 | 2000 | 400 |
| Power | In hexadecimal | Decimal value |
|---|---|---|
| 160 | 1 | 1 |
| 161 | 10 | 16 |
| 162 | 100 | 256 |
| 163 | 1000 | 4096 |
| 164 | 10000 | 65536 |
| 165 | 100000 | 1048576 |
| 166 | 1000000 | 16777216 |
| 167 | 10000000 | 268435456 |
| 168 | 100000000 | 4294967296 |
| 169 | 1000000000 | 68719476736 |
| 1610 | 10000000000 | 1099511627776 |
| 1611 | 100000000000 | 17592186044416 |
| 1612 | 1000000000000 | 281474976710656 |
A number base (radix) defines how many digits are used and what each position is worth. Decimal uses ten digits and powers of ten, binary uses just two digits and powers of two, and hexadecimal uses sixteen digits and powers of sixteen.
The value itself never changes — only how it is written. These conversions are pure integer math and exact: 255 is always 0xFF.
Hex appears everywhere in computing: CSS color codes, memory addresses, MAC addresses, and byte values. One byte (8 bits) fits exactly into two hex digits (00–FF), i.e. 0 to 255.
Number-base conversions are core to computing — decimal, binary, octal, and hexadecimal represent the same value in different bases.
255 in hexadecimal is ff (0xff).
Repeatedly divide 255 by 16 and read the remainders from bottom to top — that gives ff. The place-value table above shows each step.
255 is 0b11111111 in binary and 0xff in hexadecimal.
Hexadecimal (base 16) is compact: each hex digit maps to exactly four bits (one nibble). That is why color codes, memory addresses, and byte values are almost always written in hex — 255 is FF, far shorter than 11111111.
Yes. Converting between number bases is pure integer math and perfectly exact — the same value, just written a different way. 255 is always 0xFF.
Convert more
The number base converter covers binary, octal, decimal, and hexadecimal with an exact place-value breakdown.