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This article is first of a 3 part series about optimizing home/small office WiFi networks. First part deals with testing WiFi speed and measuring link condition, next ones will focusing on optimizing the same.

How to resr Wifi Speed

How To Test WiFi Speed:Internet speed experienced by a user connected to WiFi network depends on many factors like network congestion, distance between access point and user, number of users sharing the network etc. It also depends upon the internet connectivity available.

UPDATE:I have wrote a post about using iperf on android to measure WiFi speed.You can read the post here if interested.

First step in optimizing a WiFi network is measuring its current performance. Two approaches are available for measurement, one leverages the use of online services available in the internet while the later uses specific tools to get more accurate data.

WiFi Speed Test Method 1: Using Online Services

Many online services are available that will enable you to test your internet speed. My favorite one is speedtest.It has got a clean interface and plenty of servers to choose from. For best results choose a server which is geographically closer to you. However speed shown by such services is not exactly speed of your WiFi, but speed of your link to internet. Still this measurement can be used as a good metric in most cases.

How-To-Test-WiFi-Speed-Speedtest.net

Comparing results from multiple sites like TestMySpeed , TestMy etc will give you much more averaged values.

WiFi Speed Test Method 2: Using Specific Tools

First method won’t give you an accurate value about WiFi speed since largely link to internet providers are of much lesser bandwidth. For measuring accurate values you need two machines with traffic generator software installed. We will be using a free utility called Iperf, which is an industry recognized tool. You can download the same from here. There is no installation necessary in windows, just unzip the archive and your are ready to go.

Connect one PC to your wireless modem/router via Ethernet cable and the other PC using WiFi. In case your modem/router doesn’t have a free Ethernet port, connect both via WiFi( accuracy will be less in this case)

On the PC connected to the router via Ethernet:

Open a command prompt and move to the location where Iperf binary was extracted. Execute the following command to start iperf.

C:\<location of iperf extracted>iperf -s -u -i1

How-To-Test-WiFi-Speed-Iperf-Server

Similarly open another command prompt and type the following command to start iperf in client mode.

C:\<location of iperf extracted>iperf -c <IP OF OTHER MACHINE> -u -i1 -l 1300 -b 100m -t 600

How-To-Test-WiFi-Speed-Iperf-cClient

Command prompt with iperf running in server mode will show you present WiFi speed. Keep the client laptop at your usual browsing space and server laptop near router/modem for best results.

For those who want to explore more about iperf, an easy tutorial can be found here.

If you move around your house with your client laptop you will notice that speed will vary from position to position. For best performance you need to optimize the location of the router with respect to user location. Details about how it can be done will follow in a further post.Stay tuned!

I have wrote a post about using iperf on android to measure WiFi speed.You can read the post here if interested.

  • Reuben Rushton-Taylor

    When I tried this it just seemed to go to 100 and stay there, is there any command that wouuld go above 100? (i’m noob at this iperf)

    • Reuben Rushton-Taylor

      here

      • BT

        the -b 100m is what is limiting it to that, use a higher number to send at a higher rate. In fact, set it to 99999 and see how high your bandwidth gets. Mine got around 700 Mbits/sec.

        • BT

          Actually, i’m not quite sure iperf is testing right.. Or maybe I’m doing something wrong. Because my wireless router is only rated for 56 Mbps. I’m not using a computer connected via ethernet, i’m just running server and client (both) on the same computer over wifi. So I’d expect the counted bandwidth to be half of what it really is (counting only sending, not receiving and vice versa). Not sure what’s going on

          • Reuben Rushton-Taylor

            I’m on AC wifi which is ‘supposed’ to be 1500Mbit/s, probably much less in reality though, wanted to see what it’s real maximum was

          • Andrew Kertesz

            If you are running the server and client on the same machine, you will not get correct results as it is sending data to itself. Put the server on a wired computer in your home, then run the client on your laptop and walk around

    • Santiago Fernández Devoto

      Yeahp, me too… My router supports up to 450mbps, and I want to test that.

      • http://www.rakeshmukundan.in/ Rakesh Mukundan

        It could be because that the link between router and your server is 100Mbps ethernet, What is the link speed of your ethernet?