The fastest way to clear Firefox cache

Open Firefox and press Ctrl+Shift+Delete on Windows or Command+Shift+Delete on Mac. A window opens showing what Firefox can delete. By default, "Cached Web Content" is already checked. Click the blue "Clear Now" button and you're done — it takes a few seconds.

If you prefer the menu instead, click the three horizontal lines in the top right corner, select Settings, then Privacy & Security on the left. Scroll down to "Cookies and Site Data" and click "Clear Data". Make sure "Cached Web Content" is checked, then click "Clear".

Both methods do the same thing. The keyboard shortcut is faster if you clear cache often. The menu route is easier to remember if you do it rarely.

Key Takeaways

  • Press Ctrl+Shift+Delete (Windows) or Command+Shift+Delete (Mac) to open the cache-clearing window in one step.
  • Firefox stores cached files to load websites faster next time, but clearing them frees up disk space and can fix loading problems.
  • You can set Firefox to clear cache automatically every time you close the browser if you prefer not to do it manually.
  • Clearing cache does not delete your passwords, bookmarks, or browsing history unless you specifically check those boxes too.

What Firefox cache actually is

When you visit a website, Firefox downloads images, stylesheets, and other files to your computer and stores them in a folder called the cache. The next time you visit that same site, Firefox loads those files from your disk instead of downloading them again. This makes pages load faster.

Over time, the cache folder grows. On Windows it lives in C:\Users\[Your Name]\AppData\Local\Mozilla\Firefox\Profiles. On Mac it's in ~/Library/Caches/Firefox. You don't need to find these folders yourself — Firefox's built-in tools handle clearing them.

Clearing cache is safe. Firefox will simply re-download the files the next time you visit those sites. The only downside is that pages may load slightly slower on your first visit after clearing, because Firefox has to fetch everything fresh.

Choosing what to delete alongside cache

When you open the cache-clearing window, you'll see checkboxes for other things Firefox can delete: Cookies and Site Data, History, Autofill Form Data, Offline Website Data, and Site Settings. By default only "Cached Web Content" is checked.

Leave the others unchecked unless you have a specific reason to delete them. Deleting cookies will sign you out of websites. Deleting history removes your browsing record. Deleting autofill data removes saved addresses and credit card numbers. If you only want to free up space, clearing cache alone is enough.

The "Time range" dropdown at the top lets you clear only recent cache instead of everything. "Last Hour", "Last 24 Hours", and "Last 7 Days" are options. If you just want to clear cache from today, select "Last 24 Hours".

Setting Firefox to clear cache automatically

If you want Firefox to clear cache every time you close the browser, go to Settings > Privacy & Security and scroll to "Cookies and Site Data". Check the box that says "Delete cookies and site data when Firefox is closed".

This setting clears cookies, site data, and cached content automatically. If you only want to clear cache and not cookies, you'll need to clear manually using the keyboard shortcut or menu instead — Firefox doesn't offer a separate "clear only cache on close" option.

Automatic clearing is useful if you use Firefox on a shared computer or if you want to keep your disk space free without thinking about it. The tradeoff is that websites will load slightly slower because Firefox can't use cached files.

When clearing cache fixes common problems

If a website looks broken, loads slowly, or shows outdated information, clearing cache often fixes it. This happens because Firefox is loading an old version of the site's files from your disk instead of the current version from the web.

Clearing cache also helps if a website keeps asking you to log in even though you're already logged in, or if a page won't load at all. Sometimes a corrupted cached file causes these problems, and deleting the cache forces Firefox to download fresh files.

If clearing cache doesn't fix the problem, try disabling Firefox extensions — a misbehaving extension can also cause loading issues. You can disable them temporarily in Settings > Extensions & Themes.

The difference between cache and cookies

Cache and cookies are related but different. Cache stores website files like images and code to make pages load faster. Cookies store small text files that remember who you are — they're how websites keep you logged in and remember your preferences.

Clearing cache doesn't sign you out of websites because cookies are separate. If you clear both cache and cookies together, you will be signed out. Most of the time you only want to clear cache, not cookies.

Firefox also has a "Site Storage" section that stores data for some websites, like offline access or saved preferences. This is different from both cache and cookies. You can clear site storage separately if a particular website is misbehaving.

Frequently Asked Questions

Will clearing cache delete my passwords?

No. Passwords are stored separately from cache and are not deleted unless you specifically check the "Logins and Passwords" box, which does not appear in the standard cache-clearing window. Your saved passwords remain safe.

How much disk space does cache usually take up?

It varies depending on how much you browse, but cache typically takes between 100 MB and 1 GB. If you browse heavily or watch a lot of videos, it can grow larger. Clearing it regularly keeps Firefox running smoothly.

Can I clear cache for only one website instead of all websites?

Not through Firefox's built-in tools. You can clear all cache or nothing. If you want to clear data for a specific site, right-click on it, select "Forget About This Site", and Firefox will delete all data associated with that domain.

What's the difference between clearing cache and clearing browsing history?

Cache stores website files to make pages load faster. History is a list of websites you've visited. Clearing cache frees disk space and fixes loading problems. Clearing history removes the record of where you've been — they serve different purposes.

Does clearing cache make Firefox faster?

It can help if your cache folder has grown very large or contains corrupted files. For most users the difference is small. Clearing cache is more useful for fixing broken websites than for improving speed.