M. H., Windows keeps a record of the passwords for all the WiFi networks you've told it to, so it can connect easily. This program just digs them out in a handy way.

You can do this in a command prompt:

Type the following to see the WiFi networks it knows about:

netsh wlan show profiles

Then take the name of a WiFi network and insert it in place of {network} here, without the {}s:

netsh wlan show profile name={network} key=clear

So for example:

netsh wlan show profiles
->
Profiles on interface Wi-Fi:

Group policy profiles (read only)
---------------------------------


User profiles
-------------
All User Profile : home
All User Profile : work
All User Profile : CoffeePlace
All User Profile : FoodPlace
All User Profile : Girlfirend

netsh wlan show profile name=CoffeePlace key=clear
->
Profile CoffeePlace on interface Wi-Fi:
=======================================================================

Applied: All User Profile

Profile information
-------------------
Version : 1
Type : Wireless LAN
Name : CoffeePlace

{Bunch of information}

Security settings
-----------------
Authentication : WPA2-Personal
Cipher : CCMP
Authentication : WPA2-Personal
Cipher : GCMP
Security key : Present
Key Content : WayBetterThanStarbucks9943#@

Where the "Key Content" is the password.