| klk | Orgadata LogiKal Data |
| kll | Keyboard Layout Language File |
| klq | Kaspersky Anti-virus Quarantine File |
| klr | KeyCarbon Keystroke Log |
| klv | Sony XDCAM User Metadata |
| klw | KlattWorks Document |
| klx | Kelk 2000 Data |
| klz | Kaspersky Anti-virus Update |
| km | BMC Patrol Knowledge Module |
| km2 | ActiveModeler Process Map Data |
| kma | Correlate Knowledge Map Data |
| kmcobj | Kinemac Sprite Object |
| kmd | ABstat Batch File |
| kmd | KMD Animated Model |
| kmdi | Kermeta Data |
| kme | Kvaser Memorator Log |
| kmf | Kwalitan Memo File |
| kml | BMC Patrol Knowledge Module Library |
| kml | KEDIT Macro Library |
| kmp | Keyman Desktop Package |
| kmr | KnowledgeMill Link |
| kms | Correlate Data |
| kmx | Keyman Desktop Compiled Keyboard File |
| kmy | KMyMoney Data |
| knb | Neuro-Expert Knowledge Base Data |
| kne | iWork Keynote Encrypted Data |
| knf | Orchida Knitting System Data |
| knj | CDE Japanese Kanji Data |
| knm | iWork Keynote Macro |
| knn | Clarion Database Key Data |
| knnk | OmniPage Internal Data |
| kno | EvREsearch DigIN Serialized Break Model |
| knx | Kronos Workforce Link |
| knxprod | KNX ETS Product Database |
| kob | KASEMAKE Object |