If you notice that suddenly your Wi-Fi connection starts to run more slowly, it is likely because you are not the only person who is using it: these days, it is quite common that people use "sniffer" programs, to find out your password.
The only solution is to periodically change the password of your Wi-Fi, and for doing this there is nothing better than WiFi Key Generator.
With WiFi Key Generator is very simple to generate a hexadecimal key made from a set of keywords that you can easily remember. The security level is determined by the extension of those passwords (while most characters, less likely to external suffer infiltrations).
WiFi Key Generator avoid you doing complex calculations, but changing the password periodically depends on you. However, half of the work is guaranteed.