I need to learn how to calculate cookie/bar per attendee of an event. Is there any formula that you know of? Thanks!

are they being individually wrapped or being served on a platter type thing ? more info would help . . .

There are variables. How big is the cookie. OP mentioned platter or wrapped. Will there be other desserts available?

I hope that indydebi chimes in to help you. I know she's addressed this kind of question before. She's a caterer, so she really knows her stuff!! If she doesn't see this and answer, you might want to pm her.

At least two cookies per person! The problem is that with cookies - people might eat 6 of them.

For cookies and bars it is difficult to pin point a total. If possible you should find out who you are baking for, 1000 kids, 1000 women, 1000 truckers or combinations thereof. When I use the standard X by Y inch size measurements that all the party planning superstars out there use you're gonna almost always be wrong (unless everyone is too timid to eat). Its all a guess-timation anyway. Answering the following questions usually helps me when I guess:

Who are you baking for?
Is it self-serve?
What else will be eaten before your dessert?

After that close your eyes and pick a number.

Thanks for your responses. It's for an industry party for a film festival. There will be other light snacks. It's for several all day events and over the course of the days, they are expecting 1000 people. I appreciate your responses.