How to Technology

How to Make Your Firefox Fast Again

Written by Admin

For the last couple of weeks I had noticed my Firefox was starting to run extremely slow (hence my fun lil graphic I made above).  At one point it was taking 3-4 min to open pages that would normally open in seconds.

After many hours of learning how to fix this problem I finally found a way to make Firefox fast again.  Firefox is the second most used browser online and if you’re like me you probably prefer to use Firefox over Microsoft’s IE.

The beauty of using Firefox is it has many great add-ons that can really enhance your online browsing experience. The problem is over time these add-ons can cause your Firefox to start running slow.

Since it took me a while to figure out how to get my Firefox to stop from running so slow, I thought it would be beneficial to put an article together to help others that are experiencing this same issue.

1. Debugging Your Profile

1. Clear Your Cache

The first thing you need to do before you start installing any add-ons, extensions or tweaking your Firefox options is to clear your cache

  1. Go to “Tools” then click “Clear Recent History.”
  2. Next select “Everything” from the Time Range to Clear dropdown menu. Then place a check mark in the “cache” box area only and leave the others unchecked.

2. Run a Speed Test on Your Firefox

Now that you have cleared your cache you’re going to need to run a speed test on your browser.

  1. To do this head on over to and run a speed test on any URL like “”
  2. After you have completed the test note the time.
  3. Clear your cache again (using step outlined above). This is very important!
  4. Now close Firefox.

Next I am going to take you through a series of tweaks to optimize your Firefox to get it moving quickly again.

After you have completed some of tweaks you will come back to this step and run another speed test to compare the differences.

Step 3 – Check for Duplicate Files

The first thing you need to verify is whether or not your profile folder has any duplicate files. Mozilla application writes or creates certain files inside of your profile folder.  Sometimes these read-only or locked files may cause performance issues.

If this is the case you may see multiple numbered copies of files sitting inside of your profile folder.  What you need to do next is to verify if your files are sequentially numbered (good thing) or multiple numbered copies (bad thing).

Windows Vista Users:

  • Click the Windows Start button and type %APPDATA%\Mozilla\Firefox\Profiles\ into your Search Box (without hitting Enter). A list of profiles will appear above your Start menu (e.g. xxxxxxxx.default).
  • Click on the profile you are currently using. For most users the default profile will be the only file that has been created. After you click on your profile it will open in Windows Explorer.

Duplicate files to be aware of…

This folder is where you will see files like bookmarks.html, cert_override.txt, search.sqlite, cookies.txt and some other files and folders.

This is where you want make sure you don’t have any multiple numbered copies of any of these files. For example you should NOT see files like bookmarks{x}.html, cert_override{x}.txt, permissions{x}.sqlite, etc, where {x} represents a number.

You should also make sure there are NO temporary Mozilla files. These look like bookmarks.html.moztmp, cert_override.txt.moztmp, permissions.sqlite.moztmp, etc.  These types of files are usually only present while saving changes to a profile and are removed after changes have been completed.

What causes this problem?

If a file becomes locked or is read-only then Mozilla will automatically create a numbered files. Lets say bookmarks.html becomes locked or is read-only, then the bookmarks.html.moztmp will also become locked or read-only. So Mozilla will then create a new file called bookmarks1.html and so on.

What do I do if I find any of these files?

If you find any duplicate numbered files or Mozilla temporary files then just delete them.

If you are using Norton Antivirus, Google Desktop or Panda then make sure you remove the profile folder from their scans.  Find out more on how to do this at  MozillaZine.

2. Create a New Firefox Profile

If deleting your duplicate files didn’t help to speed up your broswer or you didn’t have any duplicate files then this next step should do the trick for you (this is what worked for me).

Setting up another profile is fairly easy to do.  If your new profile makes your Firefox run like a top again then all you need to do is transfer over some of your files from your old profile to the new one.  I’ll give you some pointers and no-no’s when moving files between old and new profiles.

Let’s Get Started…

  1. Close Firefox down by selecting File >> Exit from the menu or clicking the “X” button on the top right of your browser.
  2. Windows Vista Users: Click the Windows Start button, then type firefox -P then hit Enter. Windows XP and 2000 Users: Click the Windows Start button and select Run, then type firefox -P then hit Enter.
  3. Click the “Create Profile” button.
  4. Choose “User Profile”
  5. Click “Next” in the “Create Profile Wizard” window.
  6. Type in a new name into the “Enter New Profile Name” box and click “Finish”
  7. Uncheck the “Don’t Ask at Startup” box (you can modify this later).
  8. Finally click the “Start Firefox” box.

This will now start Firefox with your new profile.  If this solves your slow Firefox problem then you can begin to move files from your old profile to your new one you just created.

Warning Before You Move Profile Files or Folders

  • It is important that you DO NOT copy over the extensions from one profile to the other. It is best to re-install them.  Read and follow recovering important data from an old profile.
  • I highly recommend only moving over a couple files at a time and then starting up Firefox. This will allow you to pinpoint which files or folders are causing your browser to slow down.  I moved one to many over the first time I did this causing me to have to start all over again.

3. Troubleshooting Your Firefox Add-ons / Themes

As I mentioned earlier one of the reasons I love using Firefox is due to many of the great add-ons available to enhance you user experience.  This can also be a cause for slowing down the performance of your browser as well.  You can either have too many active add-ons or one or two that may be causing some sort of conflict with your version of Firefox.

To help eliminate this problem you can open your Firefox in “Safe Mode.”  By doing this you can troubleshoot various things like: modifying the defaults, resetting some of your settings, turning on and off themes or extensions. The great thing about working in this mode is you can compare behaviors in both Safe Mode and Normal Mode.

To Start Firefox in Safe Mode

  1. Close Firefox down by selecting File >> Exit from the menu or clicking the “X” button on the top right of your browser.
  2. Go to your Windows Start Button >> All Programs >> Mozilla Firefox >> Mozilla Firefox (Safe Mode).
  3. This will open Firefox in safe mode dialogue.

If your Firefox is running fast in Safe Mode then your Firefox add-ons, extensions, or themes are consuming heaving memory and time.  If this is the case I suggest you head over to Mozilla support to learn how to drop faulty extensions and update add-ons.

Closing Thoughts…

By following the steps above my Firefox is now running at top speed again.  Make sure you take your time troubleshooting through each of these areas listed above.

Let me know how these tips helped you to increase your Firefox performance.  If you have some added tips you would like to share or if I have missed something important please feel free to share with the community.

In a future blog post I will cover off some of my favorite Firefox add-ons for business and personal use. Have a great day everyone.

About the author


Dipraj has more than 4 years of Internet Marketing and Web design and development experience. He keeps up to date with all kind of news and insights of the world of internet marketing and search algorithms. Moreover he shares his own case studies, researches and advice on his and other various blogs. He is expertise at guest posting and really appreciate if someone comes up with a challenge to rank up his keywords …

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