Win 10
IE11 or Edge = Same Result
Two different computers
Fast.com
Something really wrong with this version
Hi dprout69 
Can you try to disable one Avast shield at a time, to see if that gives us a clue ?
I would try to disable Webshield first.
Greetz, Red.
Also test some of the other speed sites to see if there is a pattern.
My “official” speeds are 100/10 mbps from Time Warner cable.
On fast.com I get 53 mbps
on testmy.net I get 23.5 mbps
on speedtest.net I get the rated speed.
These tests were done in Windows XP. If I boot Windows 10 (same PC) I get the also get the rated speed on testmy.net.
Not sure why it has an issue in XP - Perhaps XP itself is the problem.
I get these speeds with avast installed, disabling the shields doesn’t make any difference.
Be Secure
Rednose
Anytime this happened in the past (not on my computer but other users that post here), it’s always the web shield and currently, in my case, that’s also what it is
davexnet
Tried different sites:
testmy.net = good
http://speedtest.bhn.net/ (brighthouse) = good
Interesting… it consistently drops it to 10 on fast.com and a couple of others on toast.net, but yet most seem normal. Disabling the web shield brings them right back up to normal though.
Could it be that webshield fool the speed test?
download a big file like 300mb and time it, then turn off webshield and repeat and time it
how big is the time difference?
I am using avast! for more than 6years and it never slowdown my net.I get 150mbps for all the time.
My suggestion is to u to turn off HTTP Scanning for a time and then look it improved or not?
Some speed test sites work incorrectly with adblocker enabled.
Try this one (HTML5) :