Did you try disabling plugins like flash and Java and see if that improves performance? Which site did you use? Try googling Speedofme and seeing if they give you different results.

Start Firefox in Safe Mode {web Link} by holding down the <Shift>
(Mac Options) key, and then starting Firefox. Is the problem still there?

Already refreshed firefox also started in safe mode also manually disabled ext. and plug ins tried about 4 different sites for speed tests still 4-6 mbps compared to chrome 29-32 mbps

What antivirus/ Internet security are you using? It may be blocking Firefox.

I would suggest for now manually setting all plug-ins to ask-to-activate or disabled if you do not use them.

I use AVG anti virus already disabled it also started firefox in safe mode which as i understand should disable ext and add ons thanks for the reply

Try to test it with a HTML5 test site.

• http://speedof.me/

You can check for problems with current Shockwave Flash plugin versions and try this:

• make sure you have the latest Flash version:
  http://www.adobe.com/special/products/flashplayer/fp_distribution3.html
• check for updates for your graphics drive drivers
  https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration
• disable hardware acceleration in the Flash plugin
  https://helpx.adobe.com/flash-player/kb/video-playback-issues.html
• disable hardware acceleration in Firefox
  https://support.mozilla.org/kb/upgrade-graphics-drivers-use-hardware-acceleration

See also:

• http://kb.mozillazine.org/Flash#Troubleshooting

speedofme test 5.90 download 2.47 upload firefox. 17.77 download 6.91 upload chrome. Did everything you suggested didn't help. speedtest.net download 4.98 upload 6.12 firefox. download 31.71 upload 6.26 chrome

Boot the computer in Windows Safe Mode with network support (press F8 on the boot screen) to see if that helps.

• http://www.bleepingcomputer.com/tutorials/how-to-start-windows-in-safe-mode/
• http://www.7tutorials.com/4-ways-boot-safe-mode-windows-10

Create a new profile as a test to check if your current profile is causing the problem.

See "Creating a profile":

• https://support.mozilla.org/kb/profile-manager-create-and-remove-firefox-profiles
• http://kb.mozillazine.org/Standard_diagnostic_-_Firefox#Profile_issues

If the new profile works then you can transfer files from a previously used profile to the new profile, but be cautious not to copy corrupted files to avoid carrying over problems.

• http://kb.mozillazine.org/Transferring_data_to_a_new_profile_-_Firefox