"Here’s a screenshot from a EarthCam livestream on Inauguration Day.
The crowd was visibly smaller than that which packed the National Mall during Barack Obama’s inaugural address in 2008, when an estimated 1.8 million turned out. It’s unclear when this screenshot was taken, as the mall could have filled more as the events got underway.
Here’s a screenshot from EarthCam a day later, when an estimated half a million people flowed through the US capital in order to raise awareness of women’s rights.
It’s difficult to take accurate headcounts at events like these, where attendees often overflow into side streets. But the aerial photos give a more clear-cut look at how crowds compared.
Organizers guessed about 200,000 would join the march in DC. By late afternoon, a city official in Washington told the Los Angeles Times that organizers upped their estimate to 500,000."