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FIREFOX speed is half of what I get with Chrome

ver4422died2
ver4422died2
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When using FIREFOX I test my speed with: speedtest.xfinity.com and I get a download speeds of between 57mps and 84mps. My service through COMCAST is supposed to be 105mps.

I am using FF version 56.0.1---62 bit, with Windows 10, on a PC hardwired to a NETGEAR CM 1000 modem that is rated for DOCSIS 3.1, NO WIFI.

When using CHROME I consistently get between 101mps to 111mps.

I have done the speed test comparisons morning, afternoon and early evening and they all remain in the same ranges. 10 minutes ago I got 62.18 with FF and 104,34 with CHROME.

Please explain the performance loss with FF and if it can be fixed.


Honestly I would switch to CHROME for good if it would allow mew to migrate all my bookmarks to CHROME. I have tried several dozen times to do that and CHROME does not accept FF bookmarks evidentially because mine won't move over.

When using FIREFOX I test my speed with: speedtest.xfinity.com and I get a download speeds of between 57mps and 84mps. My service through COMCAST is supposed to be 105mps. I am using FF version 56.0.1---62 bit, with Windows 10, on a PC hardwired to a NETGEAR CM 1000 modem that is rated for DOCSIS 3.1, NO WIFI. When using CHROME I consistently get between 101mps to 111mps. I have done the speed test comparisons morning, afternoon and early evening and they all remain in the same ranges. 10 minutes ago I got 62.18 with FF and 104,34 with CHROME. Please explain the performance loss with FF and if it can be fixed. Honestly I would switch to CHROME for good if it would allow mew to migrate all my bookmarks to CHROME. I have tried several dozen times to do that and CHROME does not accept FF bookmarks evidentially because mine won't move over.

All Replies (4)

user633449
user633449
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That is a really strange result. You are sure all conditions are the same when you test (speed test is using the same servers to run the test)? The browser you use shouldn't impact your download speeds.


Some other tips:

  • I'd suggest switching to ublock origin and uninstalling Adblock plus. Ublock is generally faster and blocks more ads by default.
  • I see you have a disabled norton extension. Norton is a pretty terrible anti-virus, so if you are using it, I'd strongly suggest uninstalling it and just using the built in windows defender anti-virus. This could explain some of the speed issues.
ver4422died2
ver4422died2 Question owner
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speed tests done within one minute of each other. adblocker plus applies to both browsers so if it effects FF more than Chrome that is a FF issue.

My speed test records go back to July 2017 and then I was getting 105+ with FF on a regular basis.

Norton is the chosen anti-virus because other brands think some of my software I use for work is a virus and won't let me use them. Besides Norton is the brand that Comcast, my ISP, uses so it is most compatible with the ISP.

Since this problem has popped up in the last week I can suspect a recent FF update to be the issue?

user633449
user633449
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There is no such thing as an anti-virus being compatible with an ISP. All anti-virus work with all ISPs. Norton is trash. Uninstall it.

I sincerely doubt this has anything to do with Firefox, I gave you some troubleshooting steps, did you try them? Also, confirm speed test is using the same servers to run the test in each browser

ver4422died2
ver4422died2 Question owner
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all speed test done the same within one minute of eachother.

not interested in your opinion of Norton.