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A file extension is a suffix at the end of a filename that indicates the file type and format. For example, .docx indicates a Microsoft Word document.

Check the file extension and use the appropriate software listed on our site. We provide compatibility information for Windows, Mac, and Linux.

On Windows, file extensions are not case sensitive, but on macOS and Linux they are. Always check the exact extension.

Try alternative software options listed on the file extension page. Some files may require specific software or codecs.