Link: RingLogix Internet Speed Test.

When setting up QoS on any router, it is equally important to setup traffic shapping. If not, all outgoing packets, whether prioritized or not, may congest your WAN uplink and create self induced packet loss.

We suggest that you run 2-3 speed test and use the average speed result as your basis. When configuring the traffic shapping it's recommended to throttle your speed to 90% of your average available speed. This is your safe harbor.  

Allowing your router to use more that this amount can create network issues that will affect your VoIP Audio Quality.

The RingLogix Internet Speed Test is available to use on any web browser. You should avoid running this test over a wifi connection or your result can be affected.