Presidential cultural heritage envoy Stephane Bern told broadcaster France-Info that �880 million ($1.38 billion) has been raised in just a day and a half since the fire. Contributions came from near and far, rich and poor from Apple and magnates who own L'Oreal, Chanel and Dior, to Catholic parishioners and others from small towns and cities around France and the world.
The French government is gathering donations and setting up a special office to deal with big-ticket offers.
Some criticism has already surfaced among those in France who say the money could be better spent elsewhere, on smaller struggling churches or workers.
Meanwhile Macron's 5-year deadline which happens to coincide with the 2024 Paris Olympics, which the government wants to make a major showcase struck many as unrealistic.
Pierluigi Pericolo, in charge of restoration and security at the St Donatian basilica in Nantes, said it could take two to five years just to secure Notre-Dame, given its size.
"It's a fundamental step, and very complex, because it's difficult to send workers into a monument whose vaulted ceilings are swollen with water," he said on France-Info. "The end of the fire doesn't mean the edifice is totally saved. The stone can deteriorate when it is exposed to high temperatures and change its mineral composition and fracture inside."
Some 30 people have already been questioned in the investigation, which the Paris prosecutor warned would be "long and complex." Among those questioned are workers at the five construction companies involved in work renovating the church spire and roof that had been under way when the fire broke out.
A plan to safeguard the masterpieces and relics was quickly put into action after the fire broke out.
The Crown of Thorns, regarded as Notre-Dame's most sacred relic, was among the treasures quickly transported after the fire broke out, authorities said. Brought to Paris by King Louis IX in the 13th century, it is purported to have been pressed onto Christ's head during the crucifixion.
The cathedral's famous 18th-century organ that boasts more than 8000 pipes also survived. Some of the paintings and other art works are being dehumidified, protected and eventually restored at the Louvre.