*All of these examples were taken wired in, to take wireless out of the equation.
First, a speedtest to Google Fiber's KC speedtest server. (speedtest.googlefiber.net) ~1 ms away
Protocol Overhead by Phil Dykstra
Next is a speedtest to Google Fiber's Mountain View speedtest server. (speed.googlefiber.net) ~40 ms away
The Google Fiber speedtest uses a different method to test download then it uses to test upload. The method they use to test download works fine with very low latency but does pretty bad at just 40ms of latency. The upload speed still looks great though.
Here's the speedtest to Google Fiber's Provo speedtest server. (provo.speedtest.googlefiber.net) ~23 ms away
In case you don't trust Google Fiber's own speedtest, here's what speedtest.net looks like. (Disclaimer: Google setup their own speedtest server for speedtest.net. It can only be used by Google Fiber customers.)
The ~800 Mbps download is odd because the exact same servers that are used for speedtest.googlefiber.net are used as speedtest servers for speedtest.net. Both speedtests were written by Ookla and use the same ports and test data.
It appears the flash speedtest that Google uses handles minor hiccups during the test much better than speedtest.net's flash speedtest does though.
My conclusion is that Google Fiber really does provide 1 Gbps down and up. Speedtests just aren't great at showing connections of that speed yet, especially over any distance.
**If you have an older computer, even if it has a gigabit network card, you won't be able to reach the max speed that Google Fiber offers with flash speedtests.
It looks like tweaks have been made to the speedtest servers. Here are new results as of 8-17-2014:
Mountain View Speedtest
Note: speed.googlefiber.net no longer points to the Mountain View speedtest server, use this link instead spd101.nuq1.googlefiber.net