Reference
File Formats
Common file extensions by category — documents, images, 3D/CAD, video, audio, archives, data.
Documents
| Extension | Name | Description |
|---|---|---|
.pdf | Portable Document Format | Fixed-layout document, cross-platform, Adobe origin (ISO 32000) |
.docx / .doc | Word Document | Microsoft Word, XML-based (docx) or legacy binary (doc) |
.txt | Plain Text | Unformatted text, no styling, universally readable |
.rtf | Rich Text Format | Basic formatted text, cross-application compatible |
.odt | OpenDocument Text | Open standard word processor format (LibreOffice) |
.xlsx / .xls | Excel Spreadsheet | Microsoft Excel, XML-based (xlsx) or legacy binary (xls) |
.pptx / .ppt | PowerPoint Presentation | Microsoft slide deck format |
.epub | Electronic Publication | Reflowable e-book format, open standard |
Images
| Extension | Name | Description |
|---|---|---|
.jpg / .jpeg | JPEG | Lossy compression, small size, no transparency |
.png | Portable Network Graphics | Lossless, supports transparency (alpha channel) |
.gif | Graphics Interchange Format | Limited 256-color palette, supports animation |
.bmp | Bitmap | Uncompressed raster, large file size |
.tiff / .tif | Tagged Image File Format | Lossless, high quality, common in print/scanning |
.webp | WebP | Modern lossy/lossless format, Google, small size |
.svg | Scalable Vector Graphics | XML-based vector image, infinitely scalable |
.psd | Photoshop Document | Layered raster editing format, Adobe |
.heic | High Efficiency Image Container | Apple's modern photo format, better compression than JPEG |
.ico | Icon | Multi-resolution icon format (favicons, app icons) |
3D & CAD
| Extension | Name | Description |
|---|---|---|
.c4d | Cinema 4D Project | Maxon Cinema 4D native scene format |
.dwg | Drawing | AutoCAD native 2D/3D drawing format |
.dxf | Drawing Exchange Format | CAD interchange format, ASCII or binary |
.stl | Stereolithography | Triangulated mesh surface, standard for 3D printing |
.obj | Wavefront OBJ | Simple 3D geometry + material format, widely supported |
.fbx | Filmbox | Autodesk format for 3D models, animation, rigging |
.step / .stp | Standard for Exchange of Product Data | ISO 10303 CAD interchange, precise solid geometry |
.iges / .igs | Initial Graphics Exchange Specification | Older CAD interchange standard |
.blend | Blender Project | Blender native scene format (open source) |
.skp | SketchUp | Trimble SketchUp native model format |
Video
| Extension | Name | Description |
|---|---|---|
.mp4 | MPEG-4 Part 14 | Most common container, H.264/H.265 codec, wide support |
.mov | QuickTime Movie | Apple container format, common in video editing |
.avi | Audio Video Interleave | Older Microsoft container, larger file size |
.mkv | Matroska | Open container, supports multiple audio/subtitle tracks |
.webm | WebM | Open web video format, VP8/VP9/AV1 codecs |
Audio
| Extension | Name | Description |
|---|---|---|
.mp3 | MPEG Audio Layer III | Lossy compression, universal compatibility |
.wav | Waveform Audio | Uncompressed, high fidelity, large file size |
.flac | Free Lossless Audio Codec | Lossless compression, smaller than WAV, same quality |
.aac | Advanced Audio Coding | Lossy, better quality-per-bit than MP3 |
.ogg | Ogg Vorbis | Open lossy format, royalty-free |
.midi / .mid | Musical Instrument Digital Interface | Note/instrument data, not audio waveform |
Archives
| Extension | Name | Description |
|---|---|---|
.zip | ZIP Archive | Most common compressed archive, native OS support |
.rar | Roshal Archive | Proprietary format (WinRAR), high compression |
.7z | 7-Zip Archive | Open format, very high compression ratio |
.tar.gz | Tarball + Gzip | Unix/Linux standard, tar bundles + gzip compresses |
.iso | Disc Image | Exact sector-copy of optical disc contents |
Data & Code
| Extension | Name | Description |
|---|---|---|
.csv | Comma-Separated Values | Plain-text tabular data, spreadsheet-compatible |
.json | JavaScript Object Notation | Lightweight structured data interchange |
.xml | Extensible Markup Language | Tag-based structured data, config, interchange |
.yaml / .yml | YAML Ain't Markup Language | Human-readable config/data format |
.sql | Structured Query Language script | Database schema/data dump or query script |