The massive event in Washington, which organisers said drew as many as half a million people, was packed with celebrities, including Madonna, Amy Schumer, America Ferrera and Ashley Judd.
Later, Trump sent a more conciliatory tweet:
"Peaceful protests are a hallmark of our democracy," he said. "Even if I don't always agree, I recognise the rights of people to express their views."
In another tweet, Trump, who yesterday accused the media of under-reporting the crowd size at his swearing-in, boasted that the television ratings for his inaugural was higher than that of President Barack Obama's swearing in four years ago.
"Wow, television ratings just out: 31 million people watched the Inauguration, 11 million more than the very good ratings from 4 years ago!" Trump wrote.
Nielsen reported that 30.6 million viewers watched inaugural coverage.
That figure was lower than Obama's first inauguration in 2009, when 38 million viewers tuned in, according to Nielsen. The record is held by Ronald Reagan, when 42 million watched his inaugural festivities in 1981.
