Speedtest.net

Has anyone else encountered the same:

I have a BT connection with STATIC IP and have confirmed it is still the same and correct. Running speedtes.net returns your IPv4 address and ISP. However, recently, it seems to return a random IP address from a different ISP ... speeds are still correct, just the data is wrong!

FOroexample, my BT v4 is 81.xxx.xxx.113 and the indication I get is "Fastly, 185.yyy.yyy.38" and a few minutes later "Fastly, 185.yyy.yyy.54"

What IP shows if you use google to “show my ip address” or any of the various IP display websites?

Are you using a Mac, or iPad, or iPhone with Apple’s new “Private Relay” service activated? Any privacy add ons in the browser, or security software that might be doing some sort of cloud based proxy?

Standard Windows PC ... everything else shows the correct IP including TBB tools. Nothing else whatsoever.

I always associate the 185 ranges with mobile networks

It is just odd, happened last week too, but different v4 address.

When I first saw it I thought my IP had changed casuing me to check it out through various means ... and all were correct.

When I just did a google on 'Fastly' a lot of the comparisons are with Cloudflare, I have to be honest I have never heard of 'Fastly'

In reply to a post by MHC:

Running speedtes.net returns your IPv4 address and ISP. However, recently, it seems to return a random IP address from a different ISP ... speeds are still correct, just the data is wrong!

Is this using speedtest.net via a browser or using their windows app or both?

Fastly ought to be renamed ‘Falsely’. At least then the results it gives could be taken in context 😎

browser only

If not already, perhaps try using their Windows app or command line tool (CLI) at the same time to see if it matches what the browser test is returning as your source address.

The obvious answers would be a proxy arrangement, a VPN service or otherwise an alternative outbound route from the usual fixed IP route that’s coming into play. You shouldn’t obviously have any CGNAT or DHCP assigned address anomalies.

Do you have any other ‘backup’ or secondary internet connection to your router like a Halo service?