Normally when your wifi is connected, you can tell how strong or weak the connection is by looking at the signal bar to see how many bars are solid, like this:
But how strong exactly?
WirelessConnectionInfo from NirSoft is a simple network tool that displays general information and statistics about your active wifi connection. One of the info listed is Signal Quality that measures the quality of signal with a number between 0 and 100. As you can see from the screenshot below, my 4 out of 5 wifi signal quality scored at 71 out of 100.
If you screen the window down, you will notice that this tool actually shows a lot more details about your Wifi connection, many of which I don’t actually know.
As NirSoft’s other tools, WirelessConnectionInfo is free and portable, and can also be run as a command-line that exports the result in a text file.