A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z | #
| K25 | Kurzweil 2500 Sample |
| K25 | Kodak DC25 Digital Camera File |
| KAR | Karaoke MIDI File |
| KB | Borland C++ Keyboard Script |
| KB | Knowledge Pro Source Code |
| KBC | Netica case knowledge base (http://www.norsys.com) |
| KBD | Keyboard Script File Layout (various) |
| KBI | Keirsey-Bates Temperament Sorter Index |
| KBM | Reflection Keyboard Script File Layout |
| KBP | Keirsey-Bates Temperament Sorter Profile |
| KBR | Keirsey-Bates Temperament Sorter Data |
| KCL | Kyoto Common LISP Source Code |
| KDC | Kodak Photo-Enhancer |
| KDO | Kudo Picture Browser |
| KEX | KEDIT Profile File |
| KEY | Forecast Pro Database |
| KEY | Keyboard Macro |
| KEY | DataCAD Icon Toolbar File |
| KEY | Program Security or Registration File (various) |
| KFX | KoFax Group 4 Image |
| KIC | Kodak Image Compression File |
| KIF | Autodesk AutoCAD Key Index File |
| KIZ | Kodak Digital Postcard File |
| KKW | RoboHELP Keyword Help Project Index File |
| KLD | KEDIT Language Definition |
| KML | KEDIT Macro Library |
| KMP | Korg Trinity KeyMaP File |
| KNO | Personal Knowbase File |
| KPG | Kai'S Power Goo Graphic |
| KPP | SmartPad Toolpad |
| KPS | IBM image |
| KQP | Konica Camera File |
| KR1 | Kurzweil 2000 Sample (multi-floppy) |
| KRZ | Kurzweil 2000 Sample |
| KSC | Korg Trinity Script |
| KSE | Keepsake Studio Export File |
| KSF | Korg Trinity Sample |
| KSH | Prodigy Internet Registration File |
| KSM | Kefrens-Sound Machine sound |
| KTT | KeyText Data File |
| KWD | Keyword |
| KWF | Delphi Pascal chart |
| KYB | Keyboard Layout |
| KYE | Kye Game Data |
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