How to check wireless speed via iPerf

Because most of the speedtest tools are just connecting from the client to the Internet, there is no way to determine whether there is a wireless or an Internet issue when the speed is low. With the help of iperf, you can test the connection from the client to the AP.

Test steps:
When testing the speed, please ensure there are no other APs on the same channel of the test AP and no other clients connected on the AP. The environment should be free from other APs or clients.

Prepare two clients for testing. One is connected on the AP directly with a cable. The other one is connected with the SSID of the AP.
To execute iperf, one of the clients will be the server. The other is the client.
Put the iperf execution file to C:\
Please open cmd in Windows OS and execute below commands on the clients acting as the iperf server.
C:\> iperf –s
You can use the computer or the mobile phone with the iperf app as an iperf client. Here is the example of how two clients executing commands for your reference.
For the Windows client (PC or a laptop) connected on the AP with wireless:
C:\> iperf -c 192.168.1.36 -P 6 -t 10 -i 1
The attached parameter means the client will connect to the server IP 192.168.136 and test for 10 seconds with 6 parallels per second.
For the mobile phone app, you can set the parameters on it directly.