File Extension Library for 96 File Types
WhatIsFileExtension keeps a free file extension library with 96 file types. Search the list or jump to a letter, then open the guide for your file.
96 of 96 file types shown
File Extension List From a to Z
Filter by family, search by name or jump to a letter. A green check marks a tested guide.
- .DATGeneric Data FileData, tested guide
- .DBFDatabase FileDatabase, tested guide
- .DBXOutlook Express FolderEmail, tested guide
- .DDDisk Duplicate FileDisk Image, tested guide
- .DEBDebian Software PackageLinux, tested guide
- DISK IMAGEGeneric Disk ImageSystem, tested guide
- .DMGApple Disk ImagemacOS, tested guide
- .DOCWord Document (Legacy)Document, tested guide
- .DOCXMicrosoft Word Open XMLDocument, tested guide
- .DRMXDrumlin Secure FileProtected, tested guide
- .DRMZDrumlin Secure PDFProtected, tested guide
- .DWGAutoCAD DrawingCAD, tested guide
- .DXLLotus Domino XMLXML, tested guide
- .E01EnCase Evidence FileForensic, tested guide
- .EDBExchange DatabaseDatabase, tested guide
- .ELFExecutable & LinkableLinux, tested guide
- .EMLEmail MessageEmail, tested guide
- .EMLXApple Mail MessageApple Mail, tested guide
- .EPUBDigital PublicationeBook, tested guide
- .ESEDBJet Blue DatabaseExtensible DB, tested guide
- .EXEWindows ExecutableExecutable, tested guide
No file type matches your search. Submit it as a new file type and our team will research it.
How to Find Your File Type in 3 Steps
Read the End of the File Name
The letters after the last dot are the extension. Windows File Explorer shows them under View, then File name extensions. Mac Finder shows them under Settings, then Advanced.
Find It in the List
Type the letters in the search box or jump to the first letter. Pages with a green check are tested guides.
Follow the Guide
Every guide names the format, the apps that open it and the checks to try first when the file fails.
What a Tested Guide Means
We build sample files or collect public ones and damage copies on purpose. Then we open every copy in the apps people use. Every tested guide reports the counts, the fixes that worked and the cases we could not solve.
See how we test every guideExamples of what we tested
- What Is an LDIF File? 55 damaged copies, two readers and a 102 line check script.
- What Is a DWG File? Tested on 141 genuine DWG files and 60 damaged copies.
- What Is an EML File? Headers, parts and how to open one.
- What Is a DBF File? 157 DBF files read in four readers.
- What Is an E01 File? 15 good and 29 damaged image sets, tested with libewf.
Need More Than a File Type Page?
File Extension Library Questions Answered
What is the file extension library?
It is a free list of 96 file types on WhatIsFileExtension. Every entry links to a page that names the format, the apps that open it and the steps to fix or convert the file.
How do you find your file type in the library?
Read the letters after the last dot in the file name. Type them in the search box above the list or use the letter links, then open the page for that file type.
What does the green check mean?
The green check marks a tested guide. We built or collected sample files for that format, damaged copies on purpose and opened every copy in the apps people use. The guide reports what we saw.
Are all 96 file types tested?
No. 41 of the 96 have a tested guide so far, and we are rebuilding the rest one at a time.
What if your file type is missing from the library?
Send it through the Submit a File Type page. Our team researches the format, tests it on our own files and adds a guide.