Can you get in to see it without booking in advance? I looked on the website and it says "Bookng Compulsory", but I also saw that for the time frame we may be there, there were 48 openings. We will be there either October 4th or 5th, but not sure which.

topping for some help

I booked in advance and had to pick up my ticket one hour before my admission time.

Even if you don't book, I would suggest that you get there one hour before the time you hope to be admitted.

I think that you should call the number listed on the webpage. My guess is that you need a day's notice at the minimum.

If you'll only be in Padova for only one day and the Chapel is important to you, you should be sure that walkin is ok -- and the only to be sure is to call them and ask them.

Hi - just to let you know that my son and I went about 5 years ago - didn't know exactly where Chapel was located, walked around and asked locals. Was told Chapel was closed by a number of locals but we persevered and finally found the Chapel. Not only was it opened but had no problems getting in.
Had to wait for about 1/2 hr. due to the introductory video and various 'air locked' rooms you had to go through prior to entering the actual Chapel.
It was quite a experience but well worth the effort! Good luck and enjoy your trip.
By the way, if in Padova and need an excellent restaurant, definitely check out La Cava! We still talk about it!