I could not be sure and I would be pretty bad at guesstimating. To do that I think that you would need to have a baseline of experience. I have been to some Life Marches, but of course those are underestimated, too.
I was in the crowds, but I didn’t it seemed all that thick when we arrived at 11:30.
The photos that I am seeing are pretty amazing and I guess that they are earlier in the day.
The other reason that it would be tough to estimate is because when I got there I noticed a good many leaving. It seemed that people were coming and going all day.
It was an awesome crowd! Lot’s of different kinds of groups represented. Great Americans!
Did you start at at Freedom Plaza and march?