File Extension Lookup

Look up common file extensions and identify file types, categories, MIME types, common uses, and related file converter tools.

Find a File Extension

Tip: You can search with or without the dot. For example, PDF, .pdf, JPG, .jpg, DOCX, and .docx will all work.
File extension details will appear here.

How the file extension lookup works

Extension search:
Enter extensions like .pdf, .jpg, .png, .docx, .xlsx, .csv, .txt, .html, .zip, or .mp4.

Category search:
Search categories like document, image, spreadsheet, text, archive, audio, video, web, code, or data.

MIME type search:
Search terms like application/pdf, image/jpeg, text/csv, or application/zip.

Program search:
Search software names like Word, Excel, Photoshop, browser, text editor, or media player.

Why use a file extension lookup?

A file extension lookup helps identify what kind of file you have, what it is commonly used for, and what tool may open or convert it.

It is useful for file converters, PDF tools, image converters, document tools, text tools, spreadsheets, downloads, attachments, and website file management.

Popular file extension lookup uses

Frequently asked questions

Is a file extension the same as a file format?

Not always. A file extension is the label at the end of a filename. The actual file format is the structure of the file itself.

Can I convert a file by renaming the extension?

Usually no. Renaming a file extension does not truly convert the file. Use a converter tool when you need a real format change.

What is a MIME type?

A MIME type is a standard label used by browsers, servers, and software to identify file content, such as application/pdf or image/jpeg.

Can I copy the lookup result?

Yes. After running a lookup, click the copy button to copy the result.