File extension helps us to identify the file types. Say we all know *.mp3 file is audio file and we need audio player to open that file. Likewise we can identify video file, audio file, images, document files and many files with which we are familiar. Mostly we also know the software name that can open this kind of files.Here are few tips by which you can deal with files with unknown extension.

1.Use Google Search To Know File Type:

Just like Google knows everything.You can use Google search to know file extension and type. Just can write extension of file in Google search and it will show you results based on your typed keyword. For example, if you type *.pdf, so it will shows results related to your extension with full details.

Google Search To identify File with Unknown Extension

You can also get list of software that can open that searched file type on Google search result.  *.pdf is just for example, you can replace pdf with your extension on google search to get exact idea about it.

2.PC Pitstop File Extension Library

It seems complete extension library there. All you need to do is just add file extension on search box and it will display all possible extension with most used application and extension related to your searched query.

Find Software For Unknown File Extension

3. is another cool web service that lets you to check the file extension for you. There is an interesting thing with this website is that is also gives download links to open software for your searched file, if available.

Openwith -free programs to open any file extension

Say, you have type .Torrent on search bar, you can see software suggestion at botton with download now button. So you can directly get software for unknown file extension.


FILExt is a file extension reference library for a mindboggling variety of file types. The site has an alphabetical index of nearly 1526 extensions. Filext currently have 26,024 records in the main database; 51,537 registered filetype records and, 16,344 records in the Program/MIME type database.

Alphabetic File Extension List


Wolframalpha is the popular website that helps users to find unknown extension online with suggestions.Wolfram won’t just reveal the technical details of that file extension – like the developer and MIME type – but also generates a list of software programs that you may use to open that file on your computer.



It regularly update its database for almost all file extensions.When you search for specific extension of file on the website, it will give you complete definition & information including  file category, Application files Application, Mime-type, application/x-ms-dos-executable Magic number, Magic string, Sample, EXE aliases and much more. the Filename Extension Database

7. contains a searchable database of thousands of file extensions with detailed information about the associated file types. You can use to look up information about unknown file types and find programs that open the files.On right sidebar, there are most commonly used file type, where you can get full information about it. - The Central File Extensions Registry

You can also download file viewer to check unknown files from your computer.File Viewer is a FREE Windows program that allows you to open all types of files.It supports over 140 different file formats and can display the contents of any file.

Related : Cloud-based File Converter To Convert Any Formats Online

Other online databases to check file extensions & file type :

Did you ever get any kind of file that you were not able to open it or search program that run that file? please share such files extension or name by commenting here.