Set a new default PDF program on Windows or Mac

Your computer has a default program — the one that launches automatically when you double-click a PDF. You can change this to any PDF reader you have installed, whether that's Adobe Reader, Microsoft Edge, Preview, or another program. The steps differ slightly between Windows and Mac, but both take less than a minute.

On Windows 10 or 11, right-click any PDF file and select "Open with" from the menu. A list of programs appears. Click "Choose another app" at the bottom. Find the program you want to use, check the box that says "Always use this app to open PDF files," and click "OK." From that point forward, all PDFs will open in that program by default.

On Mac, click any PDF file once to select it, then press Command+I to open the "Get Info" window. Look for the section labeled "Open with" and click the dropdown menu. Select the program you prefer, then click the "Change All" button. This updates the default for every PDF on your computer.

Key Takeaways

  • Windows users right-click a PDF, select "Open with," choose a program, and check "Always use this app" to set it as default.
  • Mac users select a PDF, press Command+I, pick a program from the "Open with" dropdown, and click "Change All."
  • You can change your default PDF program as many times as you want — there is no limit to switching back and forth.
  • If a program does not appear in the "Open with" list, you may need to install it first or look in your system settings for a broader default program menu.

Change defaults through your system settings instead

If right-clicking does not work or you want to set defaults for multiple file types at once, you can use your operating system's settings menu. This method also lets you see all available programs in one place, not just the ones Windows or Mac suggests.

On Windows 10 or 11, open Settings (press the Windows key and type "Settings"). Go to "Apps," then "Default apps." Scroll down and look for "PDF" in the list. Click it, and a window shows all programs that can open PDFs. Select the one you want. On some versions of Windows, you may need to click "Choose default applications by file type" instead, then find ".pdf" in the list.

On Mac, open System Preferences (or System Settings on newer versions), then click "General." Look for "Default web browser" or scroll to find file type settings. Mac's system settings are less detailed than Windows for PDF defaults, so the right-click method usually works better on Mac.

What to do if your preferred program does not appear

Sometimes the program you want to use does not show up in the "Open with" menu. This usually means Windows or Mac does not recognize it as a PDF reader, or it is not installed correctly.

First, make sure the program is actually installed. Open it directly from your Start menu (Windows) or Applications folder (Mac) to confirm it runs. If it does, close it completely, then try the right-click method again — sometimes the program only appears after it has been launched once.

If it still does not appear, uninstall and reinstall the program. On Windows, go to Settings > Apps > Apps and Features, find the program, and click "Uninstall." On Mac, drag the program from Applications to the Trash. Then read and install it fresh from the official website. After reinstalling, the program should appear in your "Open with" list.

Prevent Windows from resetting your PDF default

Windows sometimes resets your default PDF program after updates or when you install certain software. If you find your PDFs suddenly opening in a different program, Windows likely changed it automatically.

To lock in your choice, open Settings and go to "Apps" > "Default apps." Find PDF in the list and select your preferred program. Some programs, like Adobe Reader, have their own settings that let you claim PDF as the default — open the program, look for Preferences or Settings, and find an option like "Set as default PDF reader." Checking this box in the program itself often prevents Windows from overriding your choice.

If you use Microsoft Edge as your default, Windows is less likely to change it without asking, since Edge is built into the operating system.

Open a single PDF in a different program without changing the default

You do not have to change your default to open one PDF in a different program. Right-click the file and select "Open with," then choose any program from the list. That single file opens in the program you picked, but your default stays the same.

Alternatively, open the program first, then use its "File" or "Open" menu to browse for the PDF. This method works on both Windows and Mac and gives you full control over which program handles each file.

Common reasons PDFs open in the wrong program

If your PDFs keep opening in a program you did not choose, a few things might be happening. A recently installed program may have claimed PDF as its default during setup — look for a checkbox during installation that says something like "Set as default PDF reader" and uncheck it before finishing.

Windows updates sometimes reset defaults to Microsoft Edge. If this happens, use the Settings method described above to set your preferred program again. On Mac, third-party software occasionally changes defaults without asking, so check your default settings after installing new programs.

If a PDF opens in your web browser instead of a dedicated reader, your browser has claimed the PDF default. Go to your browser's settings (usually under Preferences or Settings), find the section for file types or downloads, and look for an option to stop handling PDFs. Then set your preferred program as the default using the methods above.

Frequently Asked Questions

Can I set different defaults for different types of PDFs?

No — your operating system sets one default program for all PDFs. However, you can open individual files in different programs by right-clicking and choosing "Open with" each time. Some third-party PDF managers let you organize files into folders and set rules, but the system default itself cannot be split.

What if I want PDFs to open in my web browser instead of a separate program?

On Windows, right-click a PDF, select "Open with," and choose your browser (Chrome, Firefox, Edge, etc.). Check "Always use this app" and click OK. On Mac, select a PDF, press Command+I, click the "Open with" dropdown, choose your browser, and click "Change All." Most browsers handle PDFs reasonably well, though dedicated readers often load faster.

Will changing my PDF default affect files I have already opened?

No — changing the default only affects PDFs you open going forward. Files you have already opened in another program stay in that program. The new default takes effect the next time you double-click a PDF.

Why does my PDF open in two programs at once?

This usually happens when your default program is set to a reader, but your web browser is also configured to handle PDFs. Close one of them, then check your defaults. On Windows, go to Settings > Apps > Default apps and make sure only one program is listed for PDF. On Mac, check both System Settings and your browser's preferences.

Can I undo a default change if I change my mind?

Yes — use the same method you used to change it. Right-click a PDF (Windows) or select one and press Command+I (Mac), pick the program you want to go back to, and confirm. You can switch your default as many times as you want with no restrictions.