How to Change the Default App on Mac for PDF Files

If you've ever double-clicked a PDF and watched Preview open it — when you'd rather it open in Adobe Acrobat, PDF Expert, or something else entirely — you've run into macOS's default app system. Changing it is straightforward once you know where to look, but there are a few layers to understand depending on how you want the change to apply.

What "Default App" Actually Means on macOS

When macOS opens a file, it checks the file's extension (.pdf, in this case) and looks up which application is registered to handle it. This association is stored at the system level and applies globally — meaning every PDF you double-click will open in whichever app holds that default.

Out of the box, macOS assigns Preview as the default PDF viewer. Preview is fast, lightweight, and handles basic reading and annotation well. But it doesn't support every PDF workflow — filling complex forms, signing documents with advanced tools, editing content, or working with heavily formatted files can push it beyond its limits.

That's where choosing a different default comes in.

How to Change the Default PDF App on Mac 🖥️

There are two main methods, and they both work reliably across modern macOS versions.

Method 1: Change It Through a PDF File (Recommended)

This is the most direct approach and applies the change globally to all .pdf files.

1. Find any PDF file in Finder.
2. Right-click (or Control-click) on the file.
3. Select "Get Info" from the context menu — or press Command + I.
4. In the Info panel, look for the "Open with:" section.
5. Click the dropdown menu and choose your preferred PDF application from the list.
6. Click "Change All…" to apply this as the default for every PDF, not just this one file.
7. Confirm when prompted.

If you skip "Change All," the setting only applies to that specific file — useful to know if you ever want per-file app assignments.

Method 2: Right-Click → Open With (Temporary Override)

If you just want to open a single PDF in a different app without changing the system default:

1. Right-click the PDF.
2. Hover over "Open With".
3. Select any installed application from the submenu.

This doesn't change the default — it's a one-time override. Useful when you need a specific app for one document but don't want to disrupt your usual setup.

Which PDF Apps Can You Set as Default?

Any application installed on your Mac that's registered to handle .pdf files will appear in the "Open With" dropdown. Common options include:

If an app isn't showing up in the list, it either isn't installed or hasn't been set up to declare PDF support — some apps register for .pdf files during installation, and reinstalling or updating the app can resolve this.

What Affects Which App Makes Sense as Your Default

This is where individual setups start to diverge significantly.

macOS version matters. The steps above apply to current macOS versions (Ventura, Sonoma, and similar), but older versions of macOS may label things slightly differently or organize the Info panel differently. The logic is the same; the exact labels may shift.

Installed apps and licenses. If you have Adobe Acrobat Pro through a Creative Cloud subscription, setting it as default makes sense if you're regularly editing PDFs. If you only have the free Acrobat Reader, some editing features will be unavailable regardless of it being the default opener.

File source and type. Not all PDFs are created equal. Scanned PDFs, form-fillable PDFs, PDFs with embedded multimedia, and standard text PDFs all behave differently across apps. A viewer that handles one type gracefully can struggle with another. Preview, for instance, handles scanned-image PDFs fine for viewing but has no OCR capability — meaning you can't search or copy text from a scanned document unless a separate tool processes it first.

Workflow and integration. If you work heavily in a specific ecosystem — say, an all-Apple setup with iCloud Drive and apps designed for macOS — apps built specifically for Apple platforms tend to integrate more smoothly with things like Handoff, Quick Look, and Spotlight. Cross-platform apps like Acrobat bring consistency across devices but may feel heavier in day-to-day use.

Multiple user accounts. The default app change made through "Get Info → Change All" applies to the current user account on the Mac. Other user accounts on the same machine maintain their own default app settings independently.

A Note on Browser PDF Behavior 📄

Changing the macOS default PDF app does not automatically change how your browser handles PDFs opened from the web. Browsers like Chrome, Firefox, and Safari each have their own internal PDF viewer and their own settings for whether to open PDFs inline or download them. If you want PDFs from the web to open in your chosen Mac app, you'll need to adjust each browser's download/PDF settings separately.

When the Default Keeps Reverting

Some users notice that macOS occasionally resets PDF defaults after a system update or after reinstalling an app — particularly Adobe Acrobat, which has historically been known to reassign itself as the default during updates. If you find your setting keeps changing, re-applying the "Change All" step after any major app or system update usually resolves it.

The setting itself isn't fragile — it's just that app updates can re-register file associations, effectively overwriting your preference. It's less a macOS bug and more a behavior of how certain apps handle their installation routines.

Whether Preview's built-in speed is enough, or whether a more capable app better fits your document workflow, depends on what kinds of PDFs you work with, how frequently, and what you need to do with them beyond simply reading.