said by Suit Up:
If your deviation is only 4-5ms, then that's pretty good. Right now mine is 46.651ms: even though I managed to get a min of 11.140ms, the max was still 210.431ms.
The only times I've ever seen pings that high is when I'm also up/downloading stuff. I just ran 2 tests back to back, the first one with an idle connection and the next while running a speed test (got 29.8 Mbps on my 30/5 connection BTW).
1st one, all <11.5 ms:
2nd one, while downloading at 29.8 Mbps:
So yes, if you're downloading something large then your pings will creep up. Otherwise they stay rather low. If yours are creeping while not downloading then I would replace your router as it's the most likely cause.