Turn on file extensions in File Explorer settings

Windows 11 hides file extensions by default — the part after the dot that tells you what type of file something is, like .pdf, .docx, or .exe. You can turn them back on in about 30 seconds through File Explorer's View menu.

Open File Explorer (press Windows key + E, or click the folder icon on your taskbar). At the top of the window, click the View menu. A dropdown appears with several options. Look for Show file name extensions and click it. The checkbox next to it will fill in, and from that moment on, every file on your computer will display its extension.

This setting sticks. Once you turn it on, it stays on across all folders and all future sessions — you do not have to repeat it.

Key Takeaways

  • File extensions (.pdf, .docx, .exe) are hidden by default in Windows 11, but you can show them through File Explorer's View menu in under a minute.
  • Showing extensions helps you spot suspicious files — an email attachment named "invoice.pdf.exe" is actually an executable program, not a document.
  • The setting applies to all folders and persists after you close File Explorer, so you only need to change it once.
  • If you change your mind, the same View menu lets you hide extensions again with one click.

Why you might want to see file extensions

The main reason to show extensions is security. Malware often disguises itself by using a double extension — for example, a file that looks like "Resume.pdf" in File Explorer but is actually "Resume.pdf.exe" underneath. When extensions are hidden, you see only the first part and assume it is a PDF. When they are visible, you immediately spot the .exe and know not to open it.

Extensions also help you understand what a file actually is. A file named "document" tells you nothing; "document.xlsx" tells you it is an Excel spreadsheet. This matters when you are troubleshooting, organizing files, or deciding which program to use to open something.

Some people prefer extensions hidden because they find them cluttered or unnecessary. That is a personal choice. The security benefit of seeing them usually outweighs the visual clutter, especially if you receive files from email or download them from the internet.

What to do if the View menu looks different

Depending on your Windows 11 version and recent updates, the View menu might be organized slightly differently. If you do not see Show file name extensions in the dropdown, look for a View tab at the top of File Explorer instead. Click that tab, and you will see the same option in the ribbon that appears.

Another route: click the three-dot menu icon (⋯) in the top right corner of File Explorer, then select View, then Show file name extensions. This path works in all recent versions of Windows 11.

Hiding extensions again if you change your mind

If you decide you prefer extensions hidden, the process is identical. Open File Explorer, go to View, and click Show file name extensions again. The checkbox will clear, and extensions will disappear from all your files.

You can also toggle this setting on and off as often as you like. Some people turn it on temporarily to check a suspicious file, then turn it back off. There is no penalty for switching back and forth.

How to check a file's extension without showing all extensions

If you want to see the extension of just one file without changing the global setting, right-click the file and select Properties. A window opens showing the file name, file type, and location. The file type line tells you the extension — for example, "PDF Document" or "Microsoft Word Document".

This method is slower than simply turning on extensions globally, but it works if you only need to check one or two files and do not want to change your View settings.

Common file extensions you will see

Once you turn on extensions, here are some you will encounter regularly:

  • .pdf — portable document format, used for documents that should look the same on any device
  • .docx — Microsoft Word document
  • .xlsx — Microsoft Excel spreadsheet
  • .jpg or .png — image files
  • .mp4 or .mov — video files
  • .exe — executable program (be cautious opening these from untrusted sources)
  • .zip — compressed folder containing multiple files
  • .txt — plain text file

If you see an extension you do not recognize, you can search for it online to find out what program opens it and whether it is safe.

Frequently Asked Questions

Will showing file extensions slow down my computer?

No. This is purely a display setting. It changes only what you see on screen, not how Windows stores or processes files. Your computer will run exactly the same speed whether extensions are visible or hidden.

Can I show extensions for only certain folders?

No. The View setting applies to all folders in File Explorer. Once you turn on extensions, they appear everywhere. You cannot selectively hide them in one folder and show them in another.

What if I accidentally change a file's extension?

If you rename a file and accidentally change or delete its extension, the file may stop opening in the correct program. You can fix this by right-clicking the file, selecting Rename, and typing the correct extension back in. For example, if you renamed "photo.jpg" to "photo", change it back to "photo.jpg".

Does showing extensions work the same way on external drives?

Yes. Once you turn on extensions in File Explorer, they show on all drives — your main hard drive, external USB drives, SD cards, and network locations. The setting is global to File Explorer, not specific to one drive.

Is it safe to change file extensions?

Changing an extension does not change what the file actually is — it only changes the label. Renaming "photo.jpg" to "photo.pdf" does not turn a photo into a PDF. However, changing extensions can confuse Windows about which program should open the file, so avoid renaming extensions unless you have a specific reason to do so.