Where Is My Cat is a hidden-object game that requires the player to look for 100 cats in a picture that depicts a night scene. As a result, the game displays all the cats in shades of gray, along with the suburbs of a city near major commercial areas, parks and a sports arena.
The player starts the game by using a button marked with a magnifying glass and a "+" sign to zoom in to see everything at street level instead of the birds-eye view presented at the start of the game. The player can readjust at any time by using the button marked with a magnifier and a "-" sign.
At street level, it's fairly easy for the player to notice the different cats. The animals appear in various poses in parking lots, on rooftops and motor vehicles, and in other spots. When the player selects one, a yellow rectangle appears atop it, and the number on a pawprint near the bottom-center of the image decreases by one.
Where Is My Cat offers the player one hint. After the player finds 95 cats, they can prompt the game to reveal one of the final five to them by using a button marked with a lightbulb icon.