questionable download speed

[Battius]

Sky service checker says I have 483MB download speed, but the Which speedtest says only around a 100MB download speed. service seems sluggish so I'm inclined to believe Which not Sky. Tested using a ethernet connected laptop too.
I'm on Sky Full Fibre 500
Any ideas?

[JimM1]

@Battius Was every other device disabled when you did the Ethernet test, and was your laptop capable, not running on battery also!

Use either the two test's below and post up a capture off your result's.

https://www.thinkbroadband.com/speedtest
https://speed.cloudflare.com/

[Battius]

@JimM1 re-tested this morning using thinkbroadband, ethernet connected, no other devices using, mains power source.

results as follows:

94.6MB download (bursting to 100), 67.8MB upload (bursting to 70.7) .  Would post a pic but won't let me here.

So a little similar to the one I did yesterday and way under the 500 Sky say

[JimM1]

@Battius Have to question if you have one off the two possible issues, using a fast Ethernet 100Mb/s connection, or you have a cable that is faulty, all 8 cores are required and 1 bad connection will drop the speed back to 100Mb/s speed limit, and if you are seeing it on both wired/wireless side off the network then WAN connection from the Sky Hub to the ONT is the one to go at cable wise!

[Battius]

@JimM1 Cable is sound to my knowledge and has been working well, but will double check as soon as I have a chance.

To your point, the performance has been sluggish since we moved to full fibre last week - worse than before and both wifi and wired have suffered.  TV Streaming buffering etc

Would suggest it's not the cable and more likely something else - will also check that the connection between the Hub and the ONT has any issues.

Failing that I'll just have to get an engineer out to check all that.

[JimM1]

@Battius Have a picture the other day on a posting speed related but just easier to do it again, wireless wi-fi connected on a FF500 and thinkbroadband also, will let you compare against yours! Pictures take a little time to be cleared for viewing!

On 11/10/25 at 11.33pm as an OP was complaining speed was way down.This on was 1/9/25 at 3.20pm as another compare for you!

[JimM1]

@Battius Although i no longer have my old SR203 connected this was what it was like on the service checker for speed/time!

Picture 1...Picture 2...Picture 3 and all back on Mar/Apr 2025 time scale....

[Battius]

Yes service checker looks healthy on mine too.

Very much looks like an issue between ONT and Router or ceetainly after ONT.

I think it's going to need an engineer out in all honesty.
Well certainly a call into Sky first - always a joy........