How to Clear Cache in Firefox Without Losing Your Logins

Clearing the cache is the first thing to try when a website looks broken, shows old content after an update, or won't load images. The cache is just a store of copies of pages and pictures that Firefox keeps so sites load faster. Clearing the cache does no harm, and if you tick the right box, it won't sign you out of anything. Here's how, plus the difference between cache and cookies that trips people up.

Clear the Firefox cache on a computer

1. Click the menu button, the three lines at the top right, and choose Settings. On a Mac you can also use the Firefox menu.
2. Select Privacy & Security on the left.
3. Scroll to Cookies and Site Data, sometimes labelled browsing data.
4. Click Clear Data.
5. Set the time range to Everything.
6. Tick Temporary cached files and pages and untick the rest.
7. Click Clear.

Close Settings when you're done; Firefox saves the change straight away. Reload the page that was misbehaving, holding Shift as you click reload, to make sure it fetches a fresh copy.

The quicker route through History

You can get to the same dialog faster. Press Ctrl, Shift and Delete on Windows or Command, Shift and Delete on a Mac, or open the History menu and choose Clear Recent History. Pick the time range, tick the cache option only and click Clear. It's handy when you want to clear just the last hour.

Cache, cookies and history: what each one does

Data	What it holds	What clearing it does
Cache	Saved copies of pages and images	Pages load fresh; you stay signed in
Cookies and site data	Logins, preferences, basket contents	Signs you out of websites
Browsing history	List of sites you've visited	Removes them from your history and address bar suggestions

Most problems with a single website are fixed by clearing the cache alone. Only clear cookies too if the site still misbehaves, because you'll then need to sign in everywhere again.

Clear the cache for just one website

If only one site is acting up, you don't need to clear everything. Open Settings, Privacy & Security, and in Cookies and Site Data click Manage Data. Search for the site, select it and remove it. This clears that site's stored data, including its cookies, so expect to sign in to it again, but everything else stays as it was.

Clear the cache automatically every time

In Privacy & Security, under History, change Firefox will to Use custom settings for history and tick Clear history when Firefox closes. Click Settings next to it and choose Cache only. Now the cache empties itself every time you quit Firefox, with your logins left alone. It's a good option on an older computer short of disk space.

Firefox on Android and iPhone

On Android, tap the three dots, then Settings, Delete browsing data, tick Cached images and files and tap Delete browsing data. On an iPhone, tap the menu, then Settings, Data Management, and clear Cache. The labels differ from the desktop version but the effect is the same.

Why the cache gets in the way

The cache exists to save time: instead of downloading a site's logo, styles and scripts on every visit, Firefox reuses the copies it already has. Problems start when a website changes and Firefox keeps showing the old copy. You might see a page layout that's half old and half new, buttons that don't respond, or a form that won't submit. A corrupted cache file can also stop images loading. Clearing it forces Firefox to fetch everything again, which is why it fixes so many odd faults.

If the labels on your screen are different

Firefox renames things now and then. Older versions called Settings Options and listed the cache as Cached Web Content, and newer ones may show a Clear browsing data and cookies dialog. Look for the word cache and you'll find it. If you're on a very old version, update Firefox first: open the menu, Help, then About Firefox.

When clearing the cache doesn't help

• Try the site in a Private Window; if it works there, an add-on is likely the cause.
• Disable add-ons one by one from the Add-ons and themes page.
• Clear that site's cookies too, through Manage Data.
• Check the site isn't down for everyone before you change anything else.

Cleaner apps often promise to do all this for you. Before installing one, read my take on CCleaner, because Firefox's own tools already cover what most people need.

My verdict

Clear the cache on its own first, with Everything as the time range and only the cached files box ticked. It's safe, fast and fixes most broken pages without signing you out. Use Manage Data when one site is the problem, and switch on clearing at close only if you're short of space. If you're comparing privacy browsers, my review of DuckDuckGo covers another option.

Frequently asked questions

How do I clear the cache in Firefox?

Open Settings, Privacy & Security, click Clear Data under Cookies and Site Data, tick the cached files option and click Clear.

Will clearing the Firefox cache sign me out?

No. Only clearing cookies signs you out. The cache alone doesn't.

What is the shortcut to clear cache in Firefox?

Press Ctrl, Shift and Delete on Windows, or Command, Shift and Delete on a Mac.

How do I clear the cache for one site in Firefox?

Use Manage Data in Cookies and Site Data, search for the site and remove it.

Can Firefox clear the cache automatically?

Yes. Set history to custom, tick Clear history when Firefox closes and choose Cache.

Is it safe to clear the Firefox cache?

Yes. Pages just load fresh copies the next time you visit.