How to Clear Cache & Cookies in Firefox (All Devices)

Clearing your Firefox cache and cookies frees up storage space, fixes pages that won’t load correctly, and protects your privacy by removing saved login sessions and tracking data. This guide covers the exact steps for Windows, macOS, Linux, Android, and iOS, so you can do it on any device you use.

What You’ll Need

Access to Firefox on the device you want to clear (obviously).
For Android/iOS: the Firefox app installed and updated.
For desktop: the Firefox desktop app installed.
No special permissions or passwords are required—just a few taps or clicks.

Step-by-Step

On Desktop (Windows, macOS, Linux)

Open Firefox on your computer.
Click the hamburger menu (three horizontal lines) in the top-right corner of the window.
Select Settings (on macOS, it may be under Firefox > Settings).
In the left sidebar, click Privacy & Security.
Scroll down to the Cookies and Site Data section.
Click the Clear Data… button.
A dialog box appears with two checkboxes: Cookies and Site Data and Cached Web Content. Make sure both are checked (or uncheck the one you don’t want to clear).
Click Clear.
If you want to clear everything (including browsing history, logins, etc.), go back to the History section and click Clear History…. Choose Everything from the time range dropdown, check Cookies and Cache, and click Clear Now.

On Android

Open the Firefox app on your Android phone or tablet.
Tap the three-dot menu (⋮) in the top-right corner.
Select Settings.
Tap Delete browsing data.
You’ll see a list of data types. Make sure Cookies and active logins and Cache are checked. You can also check other items like history if you want.
Tap Delete data at the bottom.
Confirm if prompted.

On iOS (iPhone/iPad)

Open the Firefox app on your iPhone or iPad.
Tap the menu icon (three horizontal lines) at the bottom-right corner of the screen.
Tap Settings (the gear icon).
Scroll down and tap Data Management.
Under Browsing Data, toggle on Cookies and Cache (and any other data you want to remove).
Tap Clear Private Data at the bottom.
Confirm by tapping Clear in the pop-up.

Common Mistakes

Clearing the wrong thing: Some users click “Clear History” and accidentally wipe their bookmarks or saved passwords. Double-check the checkboxes before confirming.
Not closing and reopening tabs: Clearing cache/cookies while a page is open may not fully apply until you refresh or restart the browser.
Assuming it logs you out of everything: Clearing cookies will log you out of most sites, which is expected. Don’t panic—just log back in.
On iOS, using the wrong menu: The settings are under the menu icon, not the system Settings app. Make sure you’re inside Firefox’s own settings.
Forgetting to clear cache on all devices: Clearing on your phone doesn’t affect your desktop. You need to repeat the process on each device.

Tips

Use the shortcut: On desktop, you can press Ctrl+Shift+Del (Windows/Linux) or Cmd+Shift+Del (macOS) to open the “Clear Recent History” window directly.
Clear only cache if you want to stay logged in: If you only need to fix a loading issue, uncheck “Cookies” and just clear the cache. This keeps your logins intact.
Set Firefox to clear automatically: In Settings > Privacy & Security, you can choose “Firefox will: Use custom settings for history” and tick “Clear history when Firefox closes” to automate the process.
Use Private Browsing for sensitive sessions: Instead of clearing after every session, use a Private Window—it doesn’t save cookies or cache in the first place.
After clearing, restart Firefox: A fresh start ensures all cached data is fully purged from memory.

Troubleshooting

If clearing cache and cookies doesn’t work as expected, try these steps:

Pages still show old content: Force-refresh the page by pressing Ctrl+F5 (Windows/Linux) or Cmd+Shift+R (macOS). If that fails, close and reopen the tab.
You’re still logged in to a site: Some sites use local storage or fingerprinting that isn’t cleared by the standard cookie clear. Go to the site’s settings (the padlock icon in the address bar) and select “Clear cookies and site data” for that specific site.
The browser is still slow: Cache and cookies are only part of the problem. Try clearing your browsing history too, or check for extensions that might be eating resources.
Can’t find the Clear Data button: On older Firefox versions, the path was different. Update Firefox to the latest version, or use the shortcut Ctrl+Shift+Del to open the clear history dialog.
On mobile, the option is grayed out: Make sure you’re not in Private Browsing mode—some options are disabled there. Exit private mode and try again.

Frequently Asked Questions

Will clearing cookies log me out of websites?

Yes. Cookies are what keep you logged in. After clearing, you’ll need to sign in again on most sites. That’s normal.

Does clearing cache delete my bookmarks or passwords?

No. Cache and cookies are separate from bookmarks and saved passwords. Unless you specifically check those options, they’ll remain untouched.

How often should I clear cache and cookies?

It depends on your usage. If you notice pages loading slowly or incorrectly, clear them. For privacy, clearing once a month is a reasonable habit. Some users do it weekly.

Can I clear cache and cookies for just one website?

Yes. On desktop, click the lock icon in the address bar, then “Clear cookies and site data” for that site. On mobile, you may need to go to Settings > Data Management and look for site-specific options, though it’s less straightforward.

Will clearing cache and cookies speed up Firefox?

Often yes, especially if the cache is bloated or corrupted. It frees up disk space and forces the browser to load fresh content, which can resolve slowdowns caused by old data.

Does clearing data on one device affect my other devices?

No. Firefox syncs bookmarks, passwords, and open tabs, but cache and cookies are stored locally on each device. You must clear them separately on every device.

General steps for current mainstream versions; menus can differ by device and version. See the disclaimer or report an error.

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