| ima | Zemax Image Surface Data |
| imap | IceWarp Mail Server IMAP Data |
| imb | IncrediMail Address Book |
| imd | Integration Manager Database |
| ime | IncrediMail Emotions Data |
| imesx | Microsoft Office IME Search Provider Definition |
| imf | IncrediMail Letter File |
| img | Magellan eXplorist Map Image |
| img3 | Apple iPhone IMG3 Data |
| img4 | Apple iPhone IMG4 Data |
| imh | IncrediMail Contacts Export Data |
| imi | Magellan eXplorist Map Image |
| imiss | PLINK Individual-based Missing Data Report |
| imk | IncrediMail License Key |
| immodules | GTK+ Input Method Modules Data |
| imn | IncrediMail Notifier |
| imotion | iClone Motion Capture Data |
| imovielibrary | iMovie Library Data |
| impx | Bentley Map Import XML Data |
| imr | Inertial Explorer IMU Data |
| ims | Adobe Premiere Media Cache |
| imsp | Survey Designer Survey Data |
| imu | Inertial Explorer Waypoint IMU Raw Data |
| imw | IncrediMail Sound File |
| in2d | Netgen 2D Geometry Data |
| in4 | InfoBlaster IN4 Data |
| in7 | OxMetrics Human-readable Data |
| ina | MS-DOS Data |
| inb | Delft3D Initial Bed Composition Data |
| inc | Altair FEKO PREFEKO Include Data |
| inc | POV-Ray Include File |
| incl | BBEdit Markup Include |
| ind | LaTeX Processed Index Data |
| ind | Maple Repository Index File |
| ind | SQL Script Indexes |