24 File Extensions starting with J
| .J | JPEG / JFIF Image |
| .J2K | LuraWave JPEG-2000 Format Image |
| .J6I | Ricoh Digital Camera Image |
| .JAR | Java Archive |
| .JAVA | JAVA Source File |
| .JBF | PaintShopPro Browser Cache File |
| .JBG | JBIG Image |
| .JBIG | JBIG Image |
| .JFIF | Joint Photographic Experts Group Image |
| .JIF | Joint Photographic Experts Group Image |
| .JIF | Jeff's Image Format Image |
| .JJ | Doodle C64 (Compressed) Image |
| .JLS | JPEG-LS Image |
| .JNG | Jpeg Network Graphics Image |
| .JP2 | LuraWave JPEG-2000 Format Image |
| .JPC | LuraWave JPEG-2000 Code Stream Image |
| .JPE | Joint Photographic Experts Group Image |
| .JPEG | Joint Photographic Experts Group Image |
| .JPG | Joint Photographic Experts Group Image |
| .JPS | Stereo Image |
| .JPX | LuraWave JPEG-2000 Format Image |
| .JS | JavaScript Source File |
| .JSP | JavaServer Pages Source File |
| .JTF | Hayes JTFax Image |