This page describes the Steam User ID and Game ID numbers and how to obtain them.
This information is useful to know when for instance looking for the userdata for a specific game.
The Steam userdata path: <Steam Installation Directory>\Steam\userdata\<Steam User ID>\<Steam Game ID>
Account ID or SteamId32 you can find in <Steam Installation Directory>\logs\connection_logs.txt
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just log in with the user you want to learn steam user ID for then lunch any game and look for the folder that got modified
If you create shortcuts on the desktop, the steam ID is in the shortcut, for example: steam://rungameid/<Game ID>
There is only 1 web service to find out steamid and info from accountid - http://steamidfinder.ru
This shows the path you would take to get to a game's userdata where some of it's saved data may be. You would replace the <Steam User ID> with your Steam ID number, not your Steam name, and <Steam Game ID> with the game's unique ID number. Read below for information on how to get this information.
Go to the store page of the game to find the Game ID. Look in the address bar of your browser. The address should look something like this.
The <Game ID> part will contain numbers. Those are the numbers you need.