Universal file icons
Computer file icon sets are typically for only a limited number of filetypes which often exclude rare or unusual filetypes. Whereas here a universal file icon set that will work with any and all filetypes can be defined as follows.
assigning 3-character file extensions
Begin by assigning every file extension a three-character name. For most file extensions with more than three characters, the extension can simply be truncated to the first three characters. Otherwise, new three-character names will need to be assigned to conflating file extensions. For example: XLS, XLSX, and XLSM can be assigned as XLS, XLX, and XLM.
One-letter and two-letter file extensions are represented here as three-letter file extensions by adding trailing zeros: M files are represented as "M00" and 7Z files are represented as "7Z0".
character mapping
Each character from 0 to Z now represents a three-digit hexatrigesimal (base-36) number. Each hexatrigesimal integer from 0 to A has to then be assigned an integer decimal (base-10) value from 0 to 255. These decimal integers are then equal to the values of 0 to FF in hexadecimal (base 16).
| base-36 number | base-10 number | base-10 color | base-16 color |
|---|---|---|---|
| 0 | 0 | 0 | 0 |
| 1 | 1 | 7 | 7 |
| 2 | 2 | 15 | F |
| 3 | 3 | 22 | 16 |
| 4 | 4 | 29 | 1D |
| 5 | 5 | 36 | 24 |
| 6 | 6 | 44 | 2C |
| 7 | 7 | 51 | 33 |
| 8 | 8 | 58 | 3A |
| 9 | 9 | 66 | 42 |
| A | 10 | 73 | 49 |
| B | 11 | 80 | 50 |
| C | 12 | 87 | 57 |
| D | 13 | 95 | 5F |
| E | 14 | 102 | 66 |
| F | 15 | 109 | 6D |
| G | 16 | 117 | 75 |
| H | 17 | 124 | 7C |
| I | 18 | 131 | 83 |
| J | 19 | 138 | 8A |
| K | 20 | 146 | 92 |
| L | 21 | 153 | 99 |
| M | 22 | 160 | A0 |
| N | 23 | 168 | A8 |
| O | 24 | 175 | AF |
| P | 25 | 182 | B6 |
| Q | 26 | 189 | Bd |
| R | 27 | 197 | C5 |
| S | 28 | 204 | CC |
| T | 29 | 211 | D3 |
| U | 30 | 219 | DB |
| V | 31 | 226 | E2 |
| W | 32 | 233 | E9 |
| X | 33 | 240 | F0 |
| Y | 34 | 248 | F8 |
| Z | 35 | 255 | FF |
file icon colors
Each three-character file extension from 000 to ZZZ now represents one of 363 = 46656 possible colors from #000000 to #ffffff.
There are still a few problems here, primarily that most file extensions do not contain decimal number characters so about 10/36 = 28% of available colors are under-utilized. The base-36 color space from 0 to Z could be contracted to just base 26 from A to Z but then the characters 0 to 9 will need to be assigned letters.
| filetype | hexcolor | color |
|---|---|---|
#000000
|
||
| 7Z | #33ff00
|
|
| HTM | #7cd3a0
|
|
#b65f6d
|
||
| SVG | #cce275
|
|
| TXT | #d3f0d3
|
|
| XLS | #f099cc
|
|
| ZZZ | #ffffff
|