Firefox includes a built-in PDF viewer to display PDF files inside the browser window. This article explains how to use the built-in PDF viewer, how to fix the common issues you might encounter, and how to use another PDF viewer.
Table of Contents
Firefox’s built-in PDF Viewer
Firefox's built-in PDF viewer allows you to view almost all PDF files found on the web without an external application (exceptions to this are PDF files with a MIME type incorrectly set). The built-in viewer is used when Portable Document Format (PDF) files are set to in your Firefox settings for different types of files. This is the default setting. When you click on a link to a PDF file or open it from the Firefox Downloads panel, it will be rendered with the built-in PDF viewer. (To learn more about the built-in viewer, see Using Firefox's built-in PDF viewer, below.)
The built-in PDF viewer will open the PDF file in Firefox without saving it.
When you're viewing a PDF file in Firefox, you can use the download button in the PDF viewer's toolbar to download and save the PDF file to your computer.
Use a different PDF viewer for downloaded PDF files
When Firefox is set as the default PDF viewer and you download a PDF file in Firefox and save it to your computer, you can use a different application to view those PDF files by following these steps:
- Open the Downloads panel by clicking the download icon next to the address bar. (Alternatively, open the Downloads Library window.)
- Right-clickHold down the control key while you click
on the download entry for the PDF file you want to open.
- Click on the context menu item for the system default PDF viewer (for example, click on ) (for example, click on ) to open the PDF file in that application.
for the PDF file entry. This will open the folder containing the downloaded file.click on the magnifying glass icon for the PDF file entry. This will open the folder containing the downloaded file in Finder. You can then right-clickcontrol-click on the file, select and choose the PDF viewer application you wish to use.Choose another PDF viewer to use by default or set Firefox to always ask
Disable the built-in PDF viewer and use another viewer
You can also set a different third-party PDF viewer to handle PDF files, instead of Firefox’s built-in PDF viewer. To switch from using the built-in PDF viewer to another viewer:
- In the Menu bar at the top of the screen, click and select .Click the menu button and select .
- In the panel, go down to the Applications section.
- Find Portable Document Format (PDF) in the list and click on the entry to select it.
- Click on the arrow under the Action column for the above entry and select the PDF viewer you wish to use from the drop-down menu.
Set Firefox to ask you what to do with PDF files
If you want Firefox to always ask you what to do with PDF files, follow the above steps to change the action for the Portable Document Format (PDF) entry, except select from the drop-down menu. The next time you click on a link to download a PDF file, Firefox will show you a prompt asking what to do with the file. You can then choose to open it with Firefox's built-in PDF viewer, open it with a different PDF application, or you can choose to save the file.
For more information, see Manage file types and download actions in Firefox.
Using Firefox's built-in PDF viewer
Fill out forms in PDF Viewer
Some PDF files have interactive fields to fill in data (such as on forms). Using Firefox's built-in PDF viewer you can fill out fields such as text, check boxes, and radio buttons. After entering data into these fields you can download the file to have the filled-out version saved to your computer.
PDF Viewer toolbar functions
- View document thumbnails or outline: The slider button on the far left will open a sidebar with thumbnails of the document's pages. Some documents will also have an outline view available. These make it easy to navigate through a long document.
- Page up and down or skip directly to a page: You can use the up and down arrows to page through a document or enter the number of the page you want to go to.
- Change the size of the document: Use the + and - buttons to zoom in and out or choose a zoom setting from the dropdown menu.
- Fullscreen or Presentation mode: Click the Presentation Mode button to allow the PDF file to take over your entire screen. Press ESC to exit fullscreen mode.
- Print: Click the Printer button to open the print setup dialog.
- Download: Click the Download button to save the PDF file to your computer.
- Copy current view: Right-clickHold down the control key while you click
the current view button to open the current view in another tab or window.
- Print: Click the Printer button to open the print setup dialog.
- Download: Click the Download button to save the PDF file to your computer.
Annotate PDF files
Click the Text button to choose a color and text size before selecting where on the document you wish to add text. Click the Draw icon to choose a color, thickness and opacity before then being able to draw on the document. Downloading the file saves a copy of the document with your annotations.
PDF Viewer keyboard shortcuts
| Command | Shortcut |
|---|---|
| Next page | N or J or → |
| Previous page | P or K or ← |
| Zoom in | Ctrl + +command + + |
| Zoom out | Ctrl + -command + - |
| Automatic Zoom | Ctrl + 0command + 0 |
| Rotate the document clockwise | R |
| Rotate counterclockwise | Shift + R |
| Switch to Presentation Mode | Ctrl + Alt + Pcommand + Alt + P |
| Choose Text Selection Tool | S |
| Choose Hand Tool | H |
| Focus the Page Number input box | Ctrl + Alt + Gcommand + Alt + G |
Troubleshoot problems with the PDF viewer
- With certain types of PDF files, the PDF Viewer may have problems displaying fonts, colors, or the whole document. If some PDF files don't render well or are blank, click the download button on the right side of the document header to open it with the default PDF viewer application on your computer.
- If you can't open any PDF files with the built-in PDF viewer, a Firefox extension could be the cause. You can disable all of your extensions, to see if one of them was the problem. For details, see Troubleshoot extensions, themes and hardware acceleration issues to solve common Firefox problems.
