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Windows uses the .pdf file association to decide which application opens a PDF when you double-click it. You can change that association from Settings, from File Explorer, or—if you are managing several PCs—from cmd.exe.
The Settings method is the clearest option on Windows 11 and Windows 10. It works with dedicated readers such as Adobe Acrobat Reader and with browsers such as Microsoft Edge or Google Chrome.
Change the default PDF viewer in Windows 11
- Open Start and select Settings.
- Go to Apps > Default apps.
- In the search box, enter
.pdf, including the period. - Select the application currently shown for the
.pdffile type. - Choose the PDF viewer you want to use. Depending on your Windows build, you may then need to select Set default or confirm the change.
Close Settings and double-click a PDF in File Explorer to test the association. If it opens in the application you selected, the change is complete.
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Change the default PDF viewer in Windows 10
- Select Start > Settings.
- Open Apps > Default apps.
- Under Set defaults for applications, use the file-type search field and search for
.pdf. - Select the current PDF application, choose the replacement viewer, and confirm the change.
You can also change the association from the application side. In Default apps, select the PDF viewer, choose Manage, find .pdf, and select the application currently assigned to it. Then choose the replacement.
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Windows 10 instructions sometimes say to open Choose default apps by file type and scroll to .pdf. That route is still applicable to Windows 10, but on Windows 11 it is usually quicker to search for .pdf directly in Apps > Default apps.
Use File Explorer instead
This is useful when you already have a PDF in front of you and want to change the association without searching through Settings.
- Open File Explorer and locate any PDF.
- Right-click the file and select Open with > Choose another app.
- Select the PDF viewer you want to use.
- Tick Always use this app to open .pdf files.
- Select OK.
If the viewer is not listed, select More apps. The list contains applications installed and registered with Windows as possible PDF handlers. If the program is not installed or has not registered itself as a PDF-capable application, it may not appear in this list.
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| Application type | What happens when it is the default |
|---|---|
| Dedicated PDF reader | PDFs open in a reader designed for printing, annotations, forms, and document navigation. |
| Microsoft Edge | PDFs open in Edge’s built-in viewer, alongside browser tabs. |
| Google Chrome or another browser | PDFs open in that browser’s built-in PDF viewer. |
| Word or Notepad | These are generally inappropriate defaults for PDFs. Reassign .pdf to a PDF-capable application. |
A browser is a valid Windows default for PDF files. You do not have to install a separate PDF reader unless you need features your browser does not provide.
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Change the association from Command Prompt
Windows has two related association layers:
assocmaps a file extension such as.pdfto a registered file type.ftypeshows or changes the command Windows uses to open that registered file type.
Both commands run in cmd.exe, not directly in PowerShell. Changes made with assoc require administrator privileges.
Check the current PDF association
- Open Command Prompt as an administrator.
- Run:
assoc .pdfThis returns the registered file type assigned to the extension. For example, the output might resemble:
.pdf=SomePdfFileTypeThe exact name depends on the installed application. Do not copy that example as a real file type on your computer.
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Pass the returned file type to ftype:
ftype SomePdfFileTypeThe result shows the command Windows uses to launch the file. In an opening command, %1 represents the filename being opened, while %* represents all supplied parameters.
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Assign a registered file type
The general assoc syntax is:
assoc [.<ext>[=<filetype>]]To assign the extension to a file type that is already registered, use:
assoc .pdf=<filetype>For example, if assoc .pdf returned ReaderPdf, the corresponding assignment would be:
assoc .pdf=ReaderPdfChanging only ftype is not enough if you do not know which extension points to that file type. Check assoc .pdf first. Incorrect manual edits can make PDFs fail to open, so Settings or File Explorer is safer for a normal desktop change.
When the change does not work
The desired viewer is missing from the list
Select More apps in the File Explorer chooser. If the program still does not appear, Windows may not have it installed or registered as a PDF handler. Repairing or reinstalling the application may register it, after which you can repeat the association change.
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PDFs still open in Word or Notepad
This is a .pdf file-association problem, not a Word or Microsoft 365 document-conversion setting. Search for .pdf in Settings > Apps > Default apps and assign it to a PDF-capable application. The File Explorer method provides a second way to set the same association.
Only browser PDFs are unaffected
The Windows default controls PDFs launched from File Explorer and other Windows file-opening actions. It does not necessarily control a PDF that is already being displayed inside a browser tab. Browsers can use their own built-in PDF viewer for documents opened from the web.
The setting is blocked
On a work or school computer, organizational policy may prevent users from changing default-app associations. If Windows refuses the change or the selection reverts, contact the device administrator.
Double-click behavior did not change
Verify that you changed the association for the .pdf extension itself. Selecting an application or changing its preferred file types is not always the same as assigning that application to .pdf. Search for .pdf in the Default apps page, then test with a locally saved PDF.
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Windows 10 support note
The procedure remains usable on Windows 10, including installations that continue to run after support ended. However, Windows 10 Home and Pro reached end of support on October 14, 2025; version 22H2 was the final release for those editions. They no longer receive normal monthly security updates after that date. LTSC editions follow separate support lifecycles.
FAQ
Can I make Chrome or Edge the default PDF viewer?
Yes. Windows can associate .pdf with Microsoft Edge, Google Chrome, or another installed browser. Search for .pdf under Settings > Apps > Default apps, select the current application, and choose the browser.
Why does Windows not show my PDF reader?
The application may not be installed, or it may not be registered with Windows as a PDF handler. Select More apps in the File Explorer chooser. If it is still absent, repair or reinstall the reader.
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Does changing the Windows default change PDFs opened in a browser?
Not necessarily. The Windows association controls files opened from File Explorer. A browser may continue using its own built-in PDF viewer for PDFs opened in a browser tab.
Is there a keyboard shortcut for changing the PDF viewer?
There is no single dedicated shortcut, but you can right-click a PDF in File Explorer and use Open with > Choose another app. Enable Always use this app to open .pdf files before selecting OK.
Can I change the default PDF viewer with a command?
You can inspect and modify the association with assoc and ftype in cmd.exe. Run assoc .pdf first. Manual changes require care and administrator privileges, so Settings is the safer option for most users.
The Bottom Line
For most Windows users, open Settings > Apps > Default apps, search for .pdf, select the current application, and choose the PDF viewer you want. The File Explorer route—Open with > Choose another app, followed by Always use this app to open .pdf files—does the same job with fewer clicks.
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