How to Clear the Cache in Firefox

Speed up your browser quickly and easily

Removing Computer Data

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Clearing the cache in Firefox isn't something you have to do every day, but it is sometimes helpful in order to solve or help prevent certain problems.

The Firefox cache contains locally saved copies of recent web pages you've visited. This is done so that the next time you visit the page, Firefox can load it from your saved copy, which will be much faster than loading it all over again from the internet.

On the other hand, if the cache doesn't update when Firefox sees a change on the website or the cached files that do load are corrupted, it can cause web pages to look and act strangely.

Instructions in this article apply to Firefox version 68.0.

Clear Temporary Internet Files Firefox

Follow the simple steps below to clear the cache from your Firefox browser, valid back through Firefox 39. It's an easy process that takes less than a minute to complete.

Clearing the cache in Firefox is completely safe and should not remove any important data from your computer. To clear the Firefox cache on your phone or tablet, check out the next section.

  1. Open Mozilla Firefox.

  2. Select the Menu button (aka the "hamburger button" from the top right of the program - the one with three horizontal lines) and then choose Options.

    Options submenu in Firefox Settings menu on Windows

    If Options is not listed in the menu, select Customize and drag Options from the list of Additional Tools and Features over to the Menu. ​

    If you're using the menu bar, choose Tools and then Options instead. You can also enter "about:preferences" in a new tab or window.​

    Firefox for Mac: On a Mac, choose Preferences from the Firefox menu and then continue as instructed below.

    Preferences menu item in Firefox for macOS
  3. Select the Privacy & Security or Privacy tab on the left.

    Privacy & Security tab on left of Options screen in Firefox
  4. Select the Clear History button in the History section.

    Clear History... button in Firefox

    If you don't see that link, change the Firefox will: option to Remember history. You can change it back to your custom setting when you're done.

  5. Set the Time range to clear: to Everything in the Clear Recent History window that appears.

    Clear Everything option in Clear Recent History dialog box in Firefox

    Doing this will remove all the cached files, but you can pick a different time range if you'd like. See Tip 5 below for more information.

  6. Clear the checkboxes for everything except for Cache in the list at the bottom of the window.

    Cache checkbox in Clear All History dialog in Firefox

    If you wish to clear other kinds of stored data, like the browsing history, feel free to check the appropriate boxes. They will be cleared along with the cache in the next step.​

    Don't see anything to check? Click the arrow next to Details.

  7. Select the Clear Now button.

    Clear Now button in Clear All History dialog in Firefox
  8. When the Clear All History window disappears, all of the files saved (cached) from your internet browsing activities in Firefox will have been removed.

If your internet cache is large, Firefox may hang while it finishes removing the files. Just be patient - it will eventually finish the job.

Clear the Cache on a Mobile Device

Clearing the cache in the Firefox mobile app is very similar to when using the desktop version. Just open the Settings menu within the Firefox app to find an option called Clear Private Data. Once there, you can choose what type of data to erase (like the cache, history, offline website data, or cookies), much like in the desktop version.

  1. Launch Firefox.

  2. Tap the hamburger menu in the lower right-hand corner. It looks like a stack of horizontal lines.

  3. Tap Settings in the slide-up menu.

  4. Swipe up to the Privacy section, then tap Data Management.

    Three iOS screens showing Firefox icon, hamburger menu, and Settings button
  5. Toggle ON or OFF the type of data you'd like to clear. Then tap the red text that says Clear Private Data.

  6. Confirm with the OK button in the next dialog.

    Three iOS screens showing Firefox settings, including Data Management, Clear Private Data and the OK confirmation button

Tips & More Information on Clearing the Cache

You can save time and clear the cache as specifically as you want with some advanced methods and shortcuts.

  • Older versions of Firefox, particularly Firefox 4 through Firefox 38, have very similar processes for clearing the cache but you should try to keep Firefox updated to the latest version if you can.
  • Using the Ctrl+Shift+Delete combination on your keyboard will immediately put you at Step 5 above.
  • If you'd rather not delete all the cache stored by Firefox, you can instead pick a different time range at Step 5. You can pick Last Hour, Last Two Hours, Last Four Hours, or Today. In each instance, Firefox will only clear the cache if the data was created within that time frame.
  • Malware can sometimes make it difficult to remove the cache in Firefox. You might find that even after you've instructed Firefox to delete the cached files, they still remain. Try scanning your computer for malicious files and then starting over from Step 1.
  • You can view cache information in Firefox by entering about:cache in the navigation bar.
  • If you hold down the Shift key while refreshing a page in Firefox (and most other web browsers), you can request the most current live page and bypass the cached version. This can be accomplished without clearing out the cache like described above.