What to Know

  • On desktop, use the Ctrl+Shift+Del (Windows) or Command+Shift+Delete (Mac) keyboard shortcut.
  • On mobile, head to Clear private data (Android) or Data Management (iOS).
  • Once there, select Cache only and then tap or click OK.

This article explains how to clear the cache in the desktop and mobile version of Firefox. The desktop directions apply to Firefox version 79 and newer. Update to the latest version of Firefox to follow along.

How to Clear the Firefox Browser Cache

Follow the simple steps below to clear the cache from the desktop software. It's an easy process that takes less than a minute to complete.

Clearing the cache is safe and shouldn't remove any useful data from your computer. Directions for clearing the Firefox cache on a phone or tablet are in the next section.

  1. Open Firefox and select the three-lined menu button in the upper-right corner of the program, then choose Settings or Options (whichever one you see in your version).

    On a Mac, open the Firefox menu and choose Preferences.

    Or, on a Windows or Mac computer, enter about:preferences in a new tab or window.​

    Options submenu in Firefox Settings menu on Windows

    If Options isn't listed in the menu, select Customize and drag Options from the list of Additional Tools and Features over to the Menu.

  2. Select the Privacy & Security or Privacy tab on the left.

    Privacy & Security tab on left of Options screen in Firefox

  3. In the History section, choose Clear History.

    Clear History... button in Firefox

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

  4. Select the Time range to clear drop-down arrow and choose Everything, or pick a different option that's relevant to how much of the cache you want to delete.

    Clear Everything option in Clear Recent History dialog box in Firefox

  5. In the History section, clear the checkboxes for everything except Cache.

    If you want to clear other stored data, like the browsing history, select the appropriate checkboxes. These are cleared with the cache in the next step.​

    Cache checkbox in Clear All History dialog in Firefox

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

  6. Select OK or Clear Now to delete everything you checked in the previous step.

    Clear Now button in Clear All History dialog in Firefox

  7. Wait for the window to disappear, which signifies that the saved files (the cache) are cleared and that you can use Firefox.

    If the internet cache is large, Firefox might hang while it finishes removing the files. Be patient—it eventually finishes the job.

Clear the Cache From the Firefox Mobile App

Clearing the cache in the Firefox mobile app is similar to the desktop version. The option to do so is in the settings, and you can choose what type of data to erase in addition to the cache, like browsing history and cookies.

  1. Tap the three-lined hamburger menu in the lower-right corner, then tap Settings.

    Three iOS screens showing Firefox icon, hamburger menu, and Settings button

  2. Select Delete browsing data on Android, or Data Management on iOS.

  3. Select Cached images and files (or just Cache if that's all you see) and any other items you want to clear.

  4. Choose Delete browsing data, Clear Private Data, or Clear Data (depending on your device), and then confirm with DELETE or OK.

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

What Is the Firefox Cache?

The Firefox cache contains locally saved copies of web pages you visited recently. This way, the next time you visit a page, Firefox loads it from the saved copy, which is faster than loading it again from the internet.

Clearing the cache doesn't need to be done every day, but it can solve or prevent certain problems. If the cache doesn't update when Firefox sees a change on the website or the cached files are corrupted, it can cause web pages to look and act strange.

What Does Cache Mean?

Tips for Clearing the Cache in Firefox

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

  • Some older versions of Firefox have similar processes for clearing the cache, but you should keep Firefox updated to the latest version.
  • Use the Ctrl+Shift+Delete combination on the keyboard to immediately go to Step 5 above.
  • If you don’t want to delete all the cache stored by Firefox, choose a different time range at Step 5. Choose either Last hour, Last two hours, Last four hours, or Today. In each instance, Firefox clears 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 instruct Firefox to delete the cached files, they still remain. Scan your computer for malicious files and then start over from Step 1.
  • To view cache information in Firefox, enter about:cache in the address bar.
  • Press and hold the Shift key while refreshing a page in Firefox (and most other web browsers) to request the most current live page and bypass the cached version. This can be accomplished without clearing out the cache as described above.

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