Wedding dessert

I would probabbly do 75-100 not everyone likes cupcakes and not everyone will eat them cuz they will be soo full

I just talked about this with a caterer today,. I'm also planning on making my own cake and there will be desserts from the caterer. We discussed it should be fair to make a cake for 75% of the guests. Not everyone has cake and I'm cool with left overs.

I have to get on the train of not having to worry about icing cupcakes the night before. If you have family helping that would change my stance (between my 2 sisters, 3 friends, mom, MIL and SIL I can see it being manageable).
If you really want to cupcakes id

We did the 1.5 rule and we had a lot left over 😂 1.5 usually allows for some guests who only eat 1 or none at all, and guests who (like me) eat 2-3+ lol

I think if you also have dessert and/or a late night snack, 1 per person is usually enough. It helps to know your guest list - do people have a sweet tooth or will do they keep sweets to a minimum? I had some younger cousins who have a sweet tooth and some of my friends do too. However most people cleared out the late night snack instead since they were craving savory over sweet after drinking a bit.

If you already have dessert and a late night snack I would think that to be safest make 1 per person, but unless you have all the RSVP's back already I would wait to make the final decission until you have that number.

I was planning on making my own cupcakes too at the beginning, but everyone talked me out of it because really I don't want to be scrambling the night before my wedding icing cupcakes lol I'd much rather be relaxing as much as possible. I was going to make enough cupcakes so that there was 1 for everyone, plus the caterer provides a dessert too, on top of having a late night snack. But now I have a professional doing the cupcakes and we're actually going with mini cupcakes instead of full sized ones which I think is more sensible given all the food. We're just making sure that there's 2 per person now since going the mini route, plus we're having an open bar and people tend to snack more while drinking so I think this is a good middle ground. So I think 1.5 per person is plenty for full sized ones

I've definitely heard the 1.5 rule, but if you're having desert already you can probably get away with 75-80% of your guest list. If people are already full and they know that more food is coming they'll be less likely to snack.
If you're worried that you'll run out and still want 1 for everyone you could get small takeaway boxes so people can pack them up and take them home. We're going to get about 2 dozen boxes just in case we have leftovers before our guests leave.
I've heard it is far more common to have leftovers than it is to run out!