As of today, the box art in this format (600x900) aren't cached, apparently. The format that is cached however, is 300x450, and is available in
C:\Program Files (x86)\Steam\appcache\librarycache\ on Windows (or
/Users/<USERNAME>/Library/Application Support/Steam/appcache/librarycache/ on MacOS, or
~/.local/share/Steam/appcache/librarycache/ on Linux).
The base URL for the box art in the format 600x900 is
<APP_ID> represents the id of the game you want. In order to get all the IDs for your game, go to your steam profile page where all your owned games are listed (
https://steamcommunity.com/profiles/USER_ID/games/?tab=all), and you can click on each game and see the app ID in the URL.
I took the freedom to create a Python3 script, to automatically fetch all the officially available full-size box art for the games in your library, and save them to a folder on your desktop.
Make sure to change
<USER_ID> in the url in the script to YOUR user ID. It can be found by using your browser, and finding your Steam account. The user ID will be the number at the end of the URL.
website = urllib.request.urlopen("https://steamcommunity.com/profiles/<USER_ID>/games/?tab=all").read().decode(
gameIDs = re.findall(r"(?:appid\":)\d+", website)
gameIDs[:] = [s.replace('appid\":', '') for s in gameIDs]
desktopfolder = os.path.expanduser('~/Desktop/steam_cover_art/')
if not os.path.exists(desktopfolder):
for i in gameIDs:
URLOpen = urllib.request.urlopen("https://steamcdn-a.akamaihd.net/steam/apps/"
+ i + "/library_600x900_2x.jpg").read()
open(desktopfolder + i + 'p.jpg', 'wb+').write(URLOpen)
except Exception as e:
ResponseData = e.read().decode("utf8", 'replace')
Not all games have official box art in this format. This is why sites like SteamGridDB have been created, in order to fill the gap.
There are also other official box art formats available, with the following URLs (the game GRID Autosport used as example):
https://steamcdn-a.akamaihd.net/steam/apps/255220/library_600x900.jpg (actually 300x450)