Cronkite's longtime chief of staff, Marlene Adler, said Cronkite died at 7:42 p.m. at his Manhattan home surrounded by family. She said the cause of death was cerebral vascular disease.
Adler said, "I have to go now" before breaking down into what sounded like a sob. She said she had no further comment.
Cronkite was the face of the "CBS Evening News" from 1962 to 1981, when stories ranged from the assassinations of President John F. Kennedy and the Rev. Martin Luther King Jr. to racial and anti-war riots, Watergate and the Iranian hostage crisis.
It was Cronkite who read the bulletins coming from Dallas when Kennedy was shot Nov. 22, 1963, interrupting a live CBS-TV broadcast of the soap opera "As the World Turns."
Cronkite was the broadcaster to whom the title "anchorman" was first applied, and he came so identified in that role that eventually his own name became the term for the job in other languages. (Swedish anchors are known as Kronkiters; In Holland, they are Cronkiters.)
"He was a great broadcaster and a gentleman whose experience, honesty, professionalism and style defined the role of anchor and commentator," CBS Corp. chief executive Leslie Moonves said in a statement.
CBS has scheduled a prime-time special, "That's the Way it Was: Remembering Walter Cronkite," for 7 p.m. Sunday.
His 1968 editorial declaring the United States was "mired in stalemate" in Vietnam was seen by some as a turning point in U.S. opinion of the war. He also helped broker the 1977 invitation that took Egyptian President Anwar Sadat to Jerusalem, the breakthrough to Egypt's peace treaty with Israel.
He followed the 1960s space race with open fascination, anchoring marathon broadcasts of major flights from the first suborbital shot to the first moon landing, exclaiming, "Look at those pictures, wow!" as Neil Armstrong stepped on the moon's surface in 1969. In 1998, for CNN, he went back to Cape Canaveral to cover John Glenn's return to space after 36 years.
"It is impossible to imagine CBS News, journalism or indeed America without Walter Cronkite," CBS News president Sean McManus said in a statement. "More than just the best and most trusted anchor in history, he guided America through our crises, tragedies and also our victories and greatest moments."
He had been scheduled to speak last January for the 50th anniversary of the U.S. Space & Rocket Center in Huntsville, Ala., but ill health prevented his appearance.
A former wire service reporter and war correspondent, he valued accuracy, objectivity and understated compassion. He expressed liberal views in more recent writings but said he had always aimed to be fair and professional in his judgments on the air.
Off camera, his stamina and admittedly demanding ways brought him the nickname "Old Ironpants." But to viewers, he was "Uncle Walter," with his jowls and grainy baritone, his warm, direct expression and his trim mustache.
When he summed up the news each evening by stating, "And THAT's the way it is," millions agreed. His reputation survived accusations of bias by Richard Nixon's vice president, Spiro Agnew, and being labeled a "pinko" in the tirades of a fictional icon, Archie Bunker of CBS's "All in the Family."
Two polls pronounced Cronkite the "most trusted man in America": a 1972 "trust index" survey in which he finished No. 1, about 15 points higher than leading politicians, and a 1974 survey in which people chose him as the most trusted television newscaster.
"He was the most trusted man in America and he was a reporter. Imagine. Who could we say that about today?" said Jeff Fager, executive producer of "60 Minutes," who began working at CBS News the year Cronkite stepped down from the anchor job.
Like fellow Midwesterner Johnny Carson, Cronkite seemed to embody the nation's mainstream. When he broke down as he announced Kennedy's death, removing his glasses and fighting back tears, the times seemed to break down with him.
And when Cronkite took sides, he helped shape the times. After the 1968 Tet offensive, he visited Vietnam and wrote and narrated a "speculative, personal" report advocating negotiations leading to the withdrawal of American troops.
"We have been too often disappointed by the optimism of the American leaders, both in Vietnam and Washington, to have faith any longer in the silver linings they find in the darkest clouds," he said, and concluded, "We are mired in stalemate."
After the broadcast, President Johnson reportedly said, "If I've lost Cronkite, I've lost middle America."
In the fall of 1972, responding to reports in The Washington Post, Cronkite aired a two-part series on Watergate that helped ensure national attention to the then-emerging scandal.
"When the news is bad, Walter hurts," the late CBS president Fred Friendly once said. "When the news embarrasses America, Walter is embarrassed. When the news is humorous, Walter smiles with understanding."
More recently, in a syndicated column, Cronkite defended the liberal record of Democratic presidential candidate John Kerry and criticized the Iraq war and other Bush administration policies.
But when asked by CNN's Larry King if that column was evidence of media bias, Cronkite set forth the distinction between opinion and reporting. "We all have prejudices," he said of his fellow journalists, "but we also understand how to set them aside when we do the job."
Cronkite was the top newsman during the peak era for the networks, when the nightly broadcasts grew to a half-hour and 24-hour cable and the Internet were still well in the future.
As many as 18 million households tuned in to Cronkite's top-rated program each evening. Twice that number watched his final show, on March 6, 1981, compared with fewer than 10 million in 2005 for the departure of Dan Rather, Cronkite's successor.
A vigorous 64 years old, Cronkite had stepped down with the assurance that other duties awaited him at CBS News, but found little demand there for his services. He hosted the shortlived science magazine series "Walter Cronkite's Universe" and was retained by the network as a consultant, although, as he was known to state wistfully, he was never consulted.
He also sailed his beloved boat, the Wyntje, hosted or narrated specials on public and cable TV, and issued his columns and the best-selling "Walter Cronkite: A Reporter's Life."
For 24 years he served as on-site host for New Year's Day telecasts by the Vienna Philharmonic, ending that cherished tradition only in 2009.
After the terrorist attacks of Sept. 11, 2001, Cronkite was selected to introduce the postponed Emmy awards show. He told the audience that in its coverage of the attack and its aftermath, "television, the great common denominator, has lifted our common vision as never before."
Cronkite joined CBS in 1950, after a decade with United Press, during which he covered World War II and the Nuremberg trials, and a brief stint with a regional radio group.
At CBS he found a respected radio-news organization dipping its toe into TV, and it put him in front of the camera. He was named anchor for CBS's coverage of the 1952 political conventions, the first year the presidential nominations got wide TV coverage. From there, he was assigned to such news-oriented programs as "You Are There" and "Twentieth Century." (He also briefly hosted a morning show, accompanied by a puppet named Charlemagne the Lion.)
On April 16, 1962, he replaced Douglas Edwards as anchor of the network's "Evening News."
"I never asked them why," Cronkite recalled in a 2006 TV portrait. "I was so pleased to get the job, I didn't want to endanger it by suggesting that I didn't know why I had it."
He was up against the NBC team of Chet Huntley and David Brinkley, which was solidly ahead in the ratings. Cronkite lacked Brinkley's wry wit and Huntley's rugged good looks, but he established himself as an anchorman to whom people could relate.
His rise to the top was interrupted just once: In 1964, disappointing ratings for the Republican National Convention led CBS boss William S. Paley to dump him as anchor of the Democratic gathering. Critics and viewers protested and he was never displaced again.
Cronkite won numerous Emmys and other awards for excellence in news coverage. In 1978, he and the evening news were the first anchorman and daily broadcast ever given a DuPont award. Other honors included the 1974 Gold Medal of the International Radio and Television Society, a 1974 George Polk journalism award and the 1969 William Allen White Award for Journalistic Merit, the first ever to a broadcaster.
His salary reportedly reaching seven figures, he was both anchorman and star interviewed by Playboy, ham enough to appear as himself on an episode of "The Mary Tyler Moore Show." But Cronkite repeatedly condemned television practices that put entertainment values ahead of news judgment.
"Broadcast journalism is never going to substitute for print," he said. "We cannot cover in depth in a half hour many of the stories required to get a good understanding of the world."
The evening news program expanded from 15 minutes to half an hour in September 1963, 17 months after Cronkite took over, but it never got to the full hour he said he needed to do a proper job.
Cronkite denied rumors that he had been forced out by Rather, but chastised him upon his 2005 departure as anchor in the wake of a disputed "60 Minutes" story about President Bush's military service.
"Dan gave the impression of playing a role, more than simply trying to deliver the news to the audience," Cronkite said. He apparently felt more warmly about Katie Couric, providing a voiceover to introduce the former "Today" show host when she debuted as the CBS anchor in 2006.
Walter Leland Cronkite Jr. was born Nov. 4, 1916, in St. Joseph, Mo., the son and grandson of dentists. The family moved to Houston when he was 10. He joked years later that he was disappointed when he "didn't see a single damn cowboy."
He got a taste of journalism at The Houston Post, where he worked summers after high school and served as campus correspondent at the University of Texas. He also did some sports announcing at a local radio station.
Cronkite quit school after his junior year for a full-time job with the Houston Press. After a brief stint at KCMO in Kansas City, Mo., he joined United Press in 1937. Dispatched to London early in World War II, Cronkite covered the battle of the North Atlantic, flew on a bombing mission over Germany and glided into Holland with the 101st Airborne Division. He was a chief correspondent at the postwar Nuremberg trials and spent his final two years with the news service managing its Moscow bureau.
Cronkite returned to the United States in 1948 and covered Washington for a group of Midwest radio stations. He then accepted Edward R. Murrow's invitation to join CBS in 1950.
In 1940, Cronkite married Mary Elizabeth "Betsy" Maxwell, whom he had met when they both worked at KCMO. They had three children, Nancy, Mary Kathleen and Walter Leland III. Betsy Cronkite died in 2005.
In his book, he paid tribute to her "extraordinarily keen sense of humor, which saw us over many bumps (mostly of my making), and her tolerance, even support, for the uncertain schedule and wanderings of a newsman."