File Extensions Reference
A reference of common file extensions and the formats they represent, documents, images, audio and video, archives, and code and data files.
A file extension is the part of a filename after the last dot. It hints at the file's
format and tells your operating system which app to open it with. The extension does not
change the actual contents, renaming a .png to .jpg does not
convert it.
Documents & text
| Extension | Format |
|---|---|
.txt | Plain text |
.pdf | Portable Document Format |
.doc / .docx | Microsoft Word |
.xls / .xlsx | Microsoft Excel spreadsheet |
.ppt / .pptx | Microsoft PowerPoint |
.odt | OpenDocument text |
.rtf | Rich Text Format |
.md | Markdown |
.csv | Comma-separated values |
.epub | E-book format |
Images
| Extension | Format |
|---|---|
.jpg / .jpeg | Compressed photo (lossy) |
.png | Lossless image with transparency |
.gif | Animated / simple images |
.webp | Modern web image format |
.svg | Scalable vector graphic (XML) |
.heic | Apple high-efficiency photo |
.tiff | High-quality print image |
.bmp | Uncompressed bitmap |
.ico | Icon (favicons) |
Audio & video
| Extension | Format |
|---|---|
.mp3 | Compressed audio |
.wav | Uncompressed audio |
.flac | Lossless audio |
.aac / .m4a | Advanced Audio Coding |
.mp4 | Video (H.264/H.265) |
.mov | Apple QuickTime video |
.mkv | Matroska video container |
.webm | Open web video |
.avi | Legacy video container |
Archives & disk
| Extension | Format |
|---|---|
.zip | Compressed archive |
.tar | Uncompressed Unix archive |
.gz | Gzip-compressed file |
.tar.gz / .tgz | Gzipped tarball |
.7z | 7-Zip archive (high ratio) |
.rar | RAR archive |
.iso | Disc image |
.dmg | Apple disk image |
Code & data
| Extension | Format |
|---|---|
.html | Web page markup |
.css | Stylesheet |
.js / .ts | JavaScript / TypeScript |
.py | Python script |
.json | JavaScript Object Notation |
.xml | Extensible Markup Language |
.yaml / .yml | YAML config |
.sql | SQL script |
.sh | Shell script |
.exe | Windows executable |
To see file extensions, enable them in your file manager (Windows
Explorer and macOS Finder hide them by default). Be cautious with executables
(.exe, .sh, .bat) from untrusted sources.
What this does
A file extensions reference maps common extensions to the formats they represent — documents, images, audio and video, archives, and code and data files.
How to use it
- Find an extension.
- Read the format it represents.
- Note the category.
- Copy the extension with one tap.
Example
.csv is a plain-text spreadsheet of comma-separated values.
Sources & methodology
Last updated .
Frequently asked questions
Does changing a file extension convert the file?
No. The extension only labels the format; renaming a .png to .jpg does not convert the contents. Use a real converter to change a file’s format.
Why can’t I see file extensions?
Windows Explorer and macOS Finder hide them by default. Enable "file name extensions" in the view settings to show them.
Which extensions should I be cautious with?
Executable types such as .exe, .bat, and .sh can run code. Only open them from sources you trust.
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