John Jay, the first Chief Justice of the United States, administered the oath of office to George Washington on April 30, 1789, at Federal Hall in New York City.

Article II, Section 1 of the United States Constitution states that the President "shall, before he enter on the Execution of his Office, take the following Oath or Affirmation:"

The exact words of the presidential oath of office are prescribed in Article II, Section 1 of the United States Constitution.

The phrase "so help me God" is not a legal requirement, but it is a traditional formality that has been used by most presidents since George Washington. It is a personal preference whether or not a president chooses to include the phrase in their oath.

George Washington was the first president to use the phrase "so help me God" in the presidential oath of office. He added the phrase at the end of the oath when he was sworn in for his second term on March 4, 1793.

George Washington was the first president to use a Bible when taking the presidential oath of office. He used a Bible that belonged to St. John's Lodge No. 1, a Masonic lodge in New York City.

Franklin D. Roosevelt was the first president to take the presidential oath of office on January 20. He took the oath on January 20, 1937, after the 20th Amendment to the Constitution was ratified, which moved the start of the presidential term from March 4 to January 20.

Richard Nixon was the first president to take the presidential oath of office in a private ceremony. He took the oath in the Blue Room of the White House on August 9, 1974, after the resignation of President Nixon.

Grover Cleveland was the first president to take the presidential oath of office twice in the same day. He took the oath on March 4, 1885, and again on March 4, 1893, after winning the presidential election in 1892.

Dwight D. Eisenhower was the first president to take the presidential oath of office in a foreign country. He took the oath on January 20, 1953, at the United States Embassy in London, England.

Ronald Reagan was the first president to take the presidential oath of office on a Sunday. He took the oath on January 20, 1985, which was a Sunday.

Barack Obama was the first president to take the presidential oath of office in the Capitol Rotunda. He took the oath on January 20, 2009, in the Rotunda of the United States Capitol.

Joe Biden was the first president to take the presidential oath of office on a digital Bible. He used an iPad to display the Bible during his inauguration on January 20, 2021.

Joe Biden was the first president to take the presidential oath of office while wearing a mask. He wore a mask during his inauguration on January 20, 2021, due to the COVID-19 pandemic.

Joe Biden was the first president to take the presidential oath of office in front of a virtual audience. Due to the COVID-19 pandemic, his inauguration on January 20, 2021, was held virtually, with a limited number of guests in attendance.