Born in Syracuse, New York on November 8, 1973 as David Jason Muir, he was raised in a village named Onondaga Hill. He is younger of the two siblings. He studied at the same place till senior high school, thereafter he went to Ithaca, New York and joined the Park school of communication of the Ithaca College. There he pursued a Bachelor of Arts degree in Journalism. During the same time he also joined the Institute of political journalism at Georgetown University and also studied at the University of Salamanca, Spain.

He started his career with WTVH television, as a reporter and anchor where he reported from Jerusalem and nearby areas. He worked for WTVH from 1995 to 2000. He then joined the WCVB television and worked there till 2003. His posting at that time was in Boston. His investigative reporting on the 9/11 hijack was appreciated and honoured by a few awards namely, the National Headliner Award , the Associated Press Honors and the regional Edward R. Murrow Award.

His journey with ABC news started in the year 2003, as an anchor for the program ‘World News Now.’ Starting from 2006, he occasionally co-anchored ‘Primetime,' a newsmagazine of ABC. In June 2007, he started anchoring for ‘World News Saturday.’ Finally in 2011, he achieved what he is famous for today i.e. he became the face of the weekend show ‘World News with David Muir.' Further in 2013, he was inducted as a co-anchor in ABC’s newsmagazine 20/20.

Muir has been a brave reporter throughout his career till date. He has fearlessly reported the situation of New Orleans from the place when Hurricane Katrina hit its coast. His courageous acts of journalism are evident from his reporting from the Israel—Lebanon border during the Israeli—Hezbollah war and reporting from Gaza strip for a coverage on Hamas. His other masterpiece reporting and investigation include reporting from Tahrir Square Egypt, Fukushima Japan, Gulf of Mexico, Haiti etc. all during the time when these places had been in distress situation either due to natural or man-made calamities. His true sense of journalism has been critically acclaimed and appreciated throughout America. His other awards and accolades include the prestigious Emmy Award, Best local newscast and best local news anchor from the Syracuse press club, honor from the Association of Radio-Television news directors.

At the age of 42, David Muir is a handsome lad, often he is known as “the Brad Pitt of news anchors." However, he never lets appreciation get over his head. He is quite a professional and down to earth man. Since he likes to keep his personal life away from limelight, it can only be speculated that he is married and has a wife. On the contrary, there have been rumours of him being gay.

Owing to numerous achievements in his profession, David Muir is believed to draw a handsome salary and his net worth is estimated to be near about $3.2 million.