What time of the day are classes least crowded?

I have pretty bad social anxiety and I have not taken a fitness class ever. I get it, no one is looking at me, it is all in my head, yada yada—but the physical feeling of anxiety defies rationality. Anyway, I thought it would be good for me to challenge myself and ease into group classes by going at a time when the room isn’t that crowded. You know, training wheels… I’m thinking 11 am is probably not so crowded but I am not so sure, so any tips appreciated. Also: which are the least crowded locations? And again: I get that no one is looking at me, etc.