| key | ArcInfo Geocoding ODB Matching Keys Data |
| ArcView Geocoding Matching Keys Data |
| Avira AntiVirus License Key |
| Concordance Database Key Fields Data |
| Crimson Editor Language Keywords Data |
| DataCAD Custom Toolbar Keys Data |
| KetuFile Encryption Key Data |
| Lightwave 3D License Key |
| OS/2 Warp Archive Key |
| SmartWare Database Key File |
| Tinker Keyword Parameters |
| Windows Registry Key Data |
| keychain | Mac OS X Keychain |
| keyhelp | UltraEdit Keyhelp Data |
| Zoom Player Keyboard Macros Data |
| keylist | UltraEdit Keylist Data |
| Zoom Player Virtual Keyboard Layout |
| keyring | Java Key Store |
| keystore | Java Key Store |
| keytab | Kerberos Encrypted Key Data |
| kez | CA 01 Customer Product Numbers Data |
| kfl | IRIS Literary Data |
| Kwalitan Filter Data |
| Pegasus Mail Auto-reply Memory Data |
| kfo | Konica Minolta Bizhub Copier Overlay Data |
| kfp | Adobe Acrobat Preflight Profile |
| kfr | Kalles Fraktaler 2 Data |
| kfs | Pegasus Mail Static Kill Data |
| kft | Matrox X.Tools Keyframe Data |
| kfx | Kofax Capabilities File |
| kgb | Kremlin Encrypt Data |
| kgf | UniCERT Key Generation Data |
| kgm | KeyTERRA-FIRMA Ground Model Data |
| kgs | Kogeo Session Data |
| kgtemp | KuGou Temporary Cache Data |
| kgv | Cisco Known Good Value Data |
| kh | Khmer-Protocols Hash Table |
| khd | Microsoft Dynamics AX Kernel Help Documentation |
| khe | kHED 3D Model Data |
| khf | Kwalitan Tree Structure |
| khi | Microsoft Dynamics AX Kernel Help Index |
| khs | Kwalitan History Data |
| khtmp | Google Earth Temporary Location Data |
| khub | Offline Course Player Data |
| khxp | HyperX NGENUITY Presets Data |
| kids | SAM Kestrel Sequence Id Data |
| 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 |
| KOFIA Log |
| kli | KalKulator Linear Algebra Data |
| 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 |
| klv | Sony XDCAM User Metadata |
| klw | KlattWorks Document |
| klx | Kelk 2000 Data |
| klz | Kaspersky Anti-virus Update |
