Aznavour, who had just returned from a concert tour of Japan, died in his home in Alpilles in south-eastern France on Monday.
He had to cancel several concerts last year after breaking his arm in a fall.
On hearing of his death, President Emmanuel Macron declared that his "masterpieces, his voice and his unique radiance will survive him for a long time".
Born Shahnour Vaghinag Aznavourian in Paris in 1924, Aznavour became one of the world's most popular singers,
Aznavour's parents were ethnic-Armenian immigrants, his father, Micha, from Akhaliskhe in Georgia, his mother Knar Baghdasarian, from Izmir in Turkey.
He became Charles thanks to a midwife who could not spell his Armenian name.
Singing father, actress mother
The couple had been waiting for a visa the US but their son's birth put a stop to that plan.
Micha worked in his father's restaurant in Paris, going on to open his own, Le Caucase, where he sang to nostalgic central European exiles.
That and the fact that Knar was an actress clearly set the boy on the path to a glittering showbiz career, which started at the age of nine, when he took the stage name Aznavour to perform at a Paris theatre.
At the age of 13 or 14 he met Maurice Chevalier but modelled his performances on another French singing start Charles Trenet, whom he said he admired for singing songs that were happy but had depth.
Performing with Piaf
Chevalier was not the only famous performer to spot Aznavour's talent and after the war he became Edith Piaf's chauffeur, secretary and confidant.
His solo career failed to take off at first but he finally won an ecstatic reception in Casablanca, during a tour that took him to several other towns there.
That led to engagements at Paris's famous Moulin Rouge and then the Olympia concert hall.
His recording career really got going in the 1960s after he signed with the Barclay label and, despite his own penchant for ballads, he wrote songs for up-and-coming rockers Johnny Hallyday and Sylvie Vartan.
The 60s also saw his reputation take off in the US, where he played to a full house at New York's Carnegie Hall, performing some songs in English.
His reputation continued to grow in France and abroad in the following decades and in the 1990s he peformed with classical musicians Luciano Pavarotti and Mstislav Rostropovich, also releasing a jazz album with guest artists including Dianne Reeves, Michel Petrucciani and Richard Galliano.
A poll by CNN and Time magazine named him Entertainer of the Century, ahead of Elvis Presley, Bob Dylan and other luminaries.
Charity, politics, tax
Aznavour was known for his charitable work, in particular after the 1988 Armenian earthquake.
President Serzh Sargsyan granted him Armenian nationality in 2008, dubbing him "a hero of the Armenian people".
His politics were on the right, he backed Valéry Giscard d'Estaing against Socialist François Mitterrand in the 1974 presidential election, performing at one of Giscard's election rallies.
But he was shocked when the far-right National Front's candidate, Jean-Marie Le Pen, reached the deciding round in the 2002 election, signing a petition condemning it and calling on all the French people to sing the Marseillaise.
He had a few run-ins with the tax authorities, being fined and given a one-year suspended prison sentence for tax avoidance in 1979 and shifting funds abroad via a company in Luxembourg, according to press revelations in 2008.
Charles Aznavour was married three times and had six children.
Charles Aznavour, a life in dates
- 22 May 1924: Born Shahnour Vaghinag Aznavourian to Micha Aznavourian and Knar Baghdasarian;
- 1933: Takes the stage name Aznavour, performs at the Théâtre du Petit Monde;
- 1935: Meets Maurice Chevalier, whom he meets several times;
- 1941: Forms a duo with Pierre Roche;
- 1946: Starts performing with Edith Piaf, marries Micheline Rugel Fromentin;
- 1947-48: Tours France, the US and Canada with Roche;
- 1948: Releases six records with Roche;
- 1950: Piaf, whose chauffeur and confidant he has become, persuades him to have plastic surgery on his nose;
- 1953: First truly successful solo concert in Casablanca;
- 1955: First television appearance, marries Evelyn Plessis;
- 1955-56: Releases several successful records;
- 1960: Signs with the Barclay record label, appears in François Truffaut’s film Tirez sur le Pianiste.
- 1963: Performs at New York’s Carnegie Hall;
- 1967: Marries Ulla Thorsell;
- 1974: She is number one in the British hit parade, 44 in the US;
- 1979: Found guilty of tax fraud, fined and given a one-year suspended prison sentence;
- 1989: Records Pour toi l’Arménie with 24 other artists in aid of victims of the Armenian earthquake the previous year;
- 1996: Named Entertainer of the Century by CNN and users of Time Online;
- 1997: Awarded the Légion d’honneur;
- 2008: Granted Armenian citizenship;
- 2017: Awarded the 2,618th star on the Hollywood Walk of Fame;
- 1 October 2018: Dies at his home in south-east France.