I actually use half a wipe at a time because I think half does an adequate job of taking all my makeup off. I just rip it down the middle and stick it back in the package. This way, I get double the amount of face wipes! I also buy the huge version from Costco so I get a lot at a time!
I use one cloth for the days I wear makeup. If I wear heavy eye make up for a smokey eye look, then I may use an extra cloth. On average, I'd say the pack lasts me a little over a month since I don't wear makeup everyday.
In a pack of 25 it takes me a couple of weeks. I usually have to use 2 at a time and since I wear make up everyday I go through them fast. But, if you don't wear make up that often or wear that much, you could make them last for quite a while.