Although modern WiFi routers or access points nowadays are able to support gigabits per second of wireless connection speed with multi-bands MU-MIMO technology, the actual network speed obtained by your connected computer / smartphone / tablet is always lower than that maximum possible speed, and is determined by the following factors:
- The location (which includes sub-factors of distance, obstacles and surrounding interference)
- The wireless chipset used and its driver efficacy
- The antenna quality
- The amount of other devices concurrently connected and sharing the same WiFi router or access point, and their network activity
There are many software tools available to help you measure your Internet connection speed, which typically involve uploading and downloading a big file to a designated server in the Internet. However, software tools that are able to measure your WiFi connection speed within your LAN using similar method are still very rare. I will introduce you 2 of them, namely DownTester and LAN Speed Test (Lite).
DownTester by NirSoft is a lightweight freeware that is able to test the download speed but not the upload speed. It performs the download speed testing by using a URL, which you need to put a large file (recommended at least 200 MB) in the computer /smartphone / tablet to be tested running either one of FTP server, HTTP server or Windows network file sharing. The ability to test using FTP or HTTP server also means that DownTester is not only able to test your LAN connection speed, but also your Internet speed when you are testing with a server located in the Internet.
Normally if you are testing the WiFi speed to a Windows laptop, you can test using Windows network file sharing. If the laptop is running Linux, you can test using its FTP, HTTP or Samba service. If it is an Android smartphone or tablet, you can install the File Manager + app which include an FTP server in its "Access from PC" function.
Then, you just need to run DownTester from a Windows laptop or PC which connected to the same LAN with your WiFi network. DownTester even comes with a portable version which can run straight away without needed to have any installation.
The screenshot above shows the DownTester result of a laptop, a smartphone and a tablet, all connected to my WiFi network using 5GHz band from different location. Although the theoretical speed of the Wireless-AC network they are connected to is up to 433Mbps (single band) or 866Mbps (dual band), their actual download speed obtained is much lower.
One thing I noticed is that, if your device is too near to your WiFi router or access point (less than 2 meter), you will get a much lower speed than when you place it further away (yet not too far until the signal is weak).
By using DownTester and test for WiFi connection speed obtained in different locations in your premise, you can find out those locations with higher speed and those with lower speed for better planning (such as where to put your 8K super-high resolution smart TV that can run YouTube and stream video from Internet).
LAN Speed Test (Lite) by Totusoft is another lightweight freeware, and it is able to test both the upload and download speed to a computer connected to your WiFi. There is another paid version called LAN Speed Test which perform almost the same thing, so I think the freeware Lite version is good enough.
LAN Speed Test (Lite) will generate the file for testing, and is able to auto delete the file after testing, so you don't need to prepare for the file. It supports 2 modes of connection: using Windows network file sharing, or connecting to a LAN Speed Test Server running in the target computer. It does not support testing using FTP or HTTP.
If you are testing using the LAN Speed Test Server method, you can perform the testing across the Internet too. However, the LAN Speed Test Server is not free.
LAN Speed Test (Lite) is portable and does not need installation. It has both Windows and Mac version.
