How to Clear Cache in Firefox on Mac (Without Logging Out of Everything)

If Firefox has started loading pages slowly, showing stale content, or behaving oddly after an update, it almost always comes down to a bloated cache. Knowing how to clear Firefox cache on Mac properly — without accidentally signing out of every website you use — is a skill worth having. This guide covers the exact steps for macOS Sequoia and Tahoe, works on both Apple Silicon and Intel Macs, and explains what each piece of stored data actually does so you delete only what you want to delete.

What Firefox Stores on Your Mac (and Where)

Firefox splits its stored data across two locations on macOS. Understanding the difference saves you from blunt-force deletions that break things unnecessarily.

The key insight: the cache lives in ~/Library/Caches/Firefox/, while passwords, bookmarks, and session cookies live in ~/Library/Application Support/Firefox/. You can safely nuke the Caches folder without touching Application Support — and Firefox will rebuild the cache the next time you browse.

How to Clear Firefox Cache on Mac Without Losing Passwords or Sessions

This is the approach most people actually want: clear accumulated junk without logging out of Gmail, GitHub, or anything else.

1. Open Firefox and press Command + Shift + Delete (or go to Firefox menu > Settings > Privacy & Security > Cookies and Site Data > Clear Data).
2. In the dialog that appears, make sure only "Cached Web Content" is checked. Uncheck "Cookies and Site Data" unless you specifically want to sign out everywhere.
3. Click Clear. Firefox clears the cache in a few seconds — no restart required.
4. Optionally, also open History > Clear Recent History (Command + Shift + Delete again, then change the time range to "Everything") if you want to clear browsing history separately.

This selective approach is the safest for day-to-day maintenance. You keep all your logins intact while reclaiming the disk space that cached assets consume.

How to Clear Firefox Cache From the Mac Finder

If Firefox is crashing and you cannot open it, or if you want to delete the cache entirely at the filesystem level, you can do it directly.

1. Quit Firefox completely (not just close the window — use Command + Q).
2. Open Finder and press Command + Shift + G to open the Go To Folder dialog.
3. Type ~/Library/Caches/Firefox/Profiles/ and press Return.
4. You will see one or more folders with names like xxxxxxxx.default-release. Open the profile folder and delete the cache2 subfolder. This is the disk cache.
5. Empty the Trash, then relaunch Firefox.

Do not delete the entire Profiles folder — that contains your bookmarks, saved passwords, and extensions. Delete only cache2 inside the profile subfolder, or the entire ~/Library/Caches/Firefox/ directory if you want a clean sweep of all cached content.

Using the Terminal Instead

If you prefer the command line, this one-liner removes the cache for the default profile while leaving everything else untouched:

rm -rf ~/Library/Caches/Firefox/Profiles/*.default-release/cache2

If you have multiple profiles, list them first:

ls ~/Library/Caches/Firefox/Profiles/

Then delete the cache2 folder from each profile you want to clean.

How Much Space Does Firefox Cache Actually Use?

On a Mac that has been in daily use for a year or more without manual cache clearing, Firefox's cache folder commonly grows to 500 MB – 2 GB. If you use Firefox for video-heavy sites or leave dozens of tabs open, it can push higher. To check the current size before deleting:

du -sh ~/Library/Caches/Firefox/

This command prints the total size of everything Firefox has cached. For a broader picture of what is consuming space across all browsers and system caches, see our guide to understanding what is taking up space on your Mac.

Clearing Firefox Cache vs. Clearing Cookies: Know the Difference

These two options sit right next to each other in Firefox's settings, and confusing them is the most common reason people accidentally sign out of everything.

• Cache: Temporary copies of web page assets — images, scripts, fonts, CSS files. Clearing this never affects your login state. Sites just reload those assets fresh from the internet on the next visit, which is why the first page load after clearing feels slightly slower.
• Cookies: Small files that websites use to remember your session. Clearing cookies signs you out of every site. Sometimes that is exactly what you want (troubleshooting, privacy), but it should be a deliberate choice.
• Site data: Includes IndexedDB, localStorage, and service-worker caches. Some progressive web apps store offline content here. Clearing it resets app state for those sites.

For routine maintenance, clearing only the cache handles the vast majority of performance issues without any collateral damage.

Setting Firefox to Clear Cache Automatically on Quit

If you prefer a zero-maintenance approach, Firefox can clear the cache every time you close it.

1. Go to Firefox > Settings > Privacy & Security.
2. Scroll to the History section.
3. Change "Firefox will" to Use custom settings for history.
4. Check Clear history when Firefox closes.
5. Click Settings… next to that option and check only "Cache". Leave cookies and passwords unchecked if you want to stay logged in.

This keeps the cache from ever accumulating while preserving sessions between launches.

Other Firefox Data Worth Auditing on Mac

Cache is usually the biggest win, but a few other Firefox folders are worth knowing about for deeper cleanups.

Crash Reports

Firefox saves detailed crash reports to ~/Library/Application Support/Firefox/Crash Reports/. Once Firefox is stable, these are safe to delete:

rm -rf "~/Library/Application Support/Firefox/Crash Reports/submitted"

Old Profile Backups

After major Firefox upgrades, the browser sometimes creates backup profile folders named *.default-release-[date] inside ~/Library/Application Support/Firefox/Profiles/. If you have confirmed your current profile is working correctly, old backups can be removed.

Extensions and Their Own Caches

Some Firefox extensions (ad blockers, translation tools) maintain their own caches inside the profile folder under storage/ or extensions/. These are generally small, but worth knowing about if you are doing a forensic cleanup.

If you want to see all of this alongside Safari, Chrome, and system-level caches in one view — with size totals and safety flags — a tool like Crumb can audit all of these at once and show what is safe to delete before anything is removed.

For a complete picture of system and app cache locations beyond the browser, see how to clear system cache on Mac.

When Clearing Cache Is Not Enough

If clearing the cache does not fix the Firefox problem you are experiencing, consider these next steps:

• Refresh Firefox: Go to about:support in the address bar and click Refresh Firefox. This resets Firefox to default settings while preserving bookmarks and passwords — more thorough than a cache clear, less drastic than a full reinstall.
• Check for extension conflicts: Open Firefox in Safe Mode (hold Option while launching on Mac) to disable all extensions and see if the problem disappears.
• Reinstall Firefox: Download a fresh copy from mozilla.org. Your profile data in ~/Library/Application Support/Firefox/Profiles/ is untouched by an app reinstall, so bookmarks and passwords survive.
• Check available disk space: Firefox slows down significantly when macOS has less than a few gigabytes free. If the disk is nearly full, clearing the cache helps but may not be sufficient on its own.