| kif | Autodesk AutoCAD Key Index File Format Data |
| kim | Commodore KIM-1 Image |
| kin | Kinemage Protein Structure Image |
| kine | KineMaster Data |
| kip | OA-KIP Client Data Transfer File |
| kipf | Kemper Profiler Presets Data |
| kipr | Kemper Profiler Profile Data |
| kipx | QQ Messenger Theme Data |
| kir | Kiruna Magnetometer Data |
| kismac | KisMAC Webservice |
| kiwi | KiwiViewer Scene |
| kjb | Kettle Job File |
| kjv | theWord King James Version Module |
| kk0 | KFK File Splitter Splitted Data |
| kk1 | ViewChoice KK1 Data |
| kk2 | ViewChoice KK2 Data |
| kkk | Filmetrics F20 Material Data |
| kkw | Adobe RoboHelp Keyword Help Project Index |
| kla | KLARFF Map Data |
| klb | KidPix Stamp Album |
| klf | KaloMa Data File |
| klg | General Log |
| klg | KOFIA Log |
| kli | KalKulator Linear Algebra Data |
| kli | WUFI Climate Data |
| klip | KlipFolio Klip |
| klk | Orgadata LogiKal Data |
| kll | Keyboard Layout Language File |
| klq | Kaspersky Anti-virus Quarantine File |
| klr | KeyCarbon Keystroke Log |
