File extensions start with character 'K'
| File Type | Category | File Format | |
|---|---|---|---|
| .kap | Data Files | BSB Chart Image File | |
| .kar | MIDI Files | Karaoke MIDI File | |
| .kbs | Data Files | Keyboard Script File | |
| .kdbx | Data Files | KeePass Password Database | |
| .kdc | Data Files | Kaspersky Virus Database File | |
| .kde | Kaspersky Data Files | KryptoStorage Container File | |
| .kdenlive | Digital Video Files | Kdenlive Project File | |
| .kdz | Kaspersky Data Files | Kaspersky Virus Bases File | |
| .key | Microsoft Files | Keynote Presentation | |
| .kgb | Compressed Files | KGB Archive File | |
| .kid | Data Files | Kidspiration Document | |
| .kismac | Data Files | KisMAC Webservice File | |
| .klg | Text Files | Log File | |
| .kml | eBook Files | Keyhole Markup Language File | |
| .kmz | Google Files | Google Earth Placemark File | |
| .knt | Text Files | KeyNote Note File | |
| .kon | Text Files | Yahoo! Widget XML File | |
| .koob | eBook Files | Koob E-Book File | |
| .kpf | Data Files | Komodo Project File | |
| .kpl | Development Files | Kids Programming Language File | |
| .kpp | Data Files | Kid Pix Presentation | |
| .kpr | Data Files | KPresenter Presentation | |
| .kpx | Data Files | Kid Pix Picture | |
| .kpz | Data Files | Komodo Template File | |
| .krz | Audio Files | Kurzweil K2000 File | |
| .ks | Microsoft Files | Kickstart File | |
| .ksf | Audio Files | Korg Trinity/Triton Sample File | |
| .kth | Data Files | Keynote Theme | |
| .kvtml | Data Files | KWordQuiz File | |
| .kwd | Text Files | KWord Document | |
| .kz | Archive Files | KuaiZip Compressed File |