You double-click a PDF and it opens in Microsoft Edge. Or you click a PDF link and it opens in a browser tab when you wanted it downloaded. Browsers became the default PDF viewer on many systems, which is convenient until you need features they lack. Here is how to change the behaviour on each platform.
Windows 11: change the default app
- Right-click any PDF and choose Open with → Choose another app.
- Select your preferred app (Acrobat Reader, Foxit, SumatraPDF, etc.).
- Click Always.
Or go to Settings → Apps → Default apps, search for .pdf, and pick the app. Windows updates sometimes reset this to Edge, so it is worth checking after a major update.
Mac: change the default app
- Select a PDF in Finder and press Cmd+I (Get Info).
- Under Open with, choose the app.
- Click Change All… and confirm.
Stop Chrome opening PDFs in a tab
- Open Settings → Privacy and security → Site settings → Additional content settings → PDF documents.
- Select Download PDFs.
PDF links will now download, and open in your default app when clicked in the downloads list.
Stop Edge opening PDFs in a tab
- Open Settings → Cookies and site permissions → PDF documents.
- Turn on Always download PDF files.
Stop Firefox opening PDFs in a tab
- Open Settings → General → Files and Applications.
- Find Portable Document Format (PDF) and change the action to Save File or Use [your app].
Safari on Mac
Safari shows PDFs inline. To download instead, right-click the link and choose Download Linked File, or hold Option while clicking.
Android
- Open Settings → Apps → Default apps (or open the app currently opening PDFs, then Open by default → Clear defaults).
- Open a PDF; Android asks which app to use. Choose one and tap Always.
Menus vary by manufacturer.
iPhone and iPad
iOS has no global default for PDFs. Instead, use the Share button on a PDF and pick the app you want, or save to Files and open it there.
When the browser is actually the better choice
Browsers open PDFs quickly and safely, since their viewers do not run PDF JavaScript, which reduces some security risks. See PDF JavaScript security risks. For editing in the browser without uploading, a tool like Docento.app adds signing, text and annotations that built-in viewers lack.
Takeaway
Set your default app in the operating system, and tell your browser to download PDFs instead of opening them. Recheck after big updates, which sometimes reset defaults. If a PDF will not open at all, see why won't my PDF open?.