The centrist's emphatic victory, which also smashed the dominance of France's mainstream parties, will bring huge relief to European allies who had feared another populist upheaval to follow Britain's vote to quit the EU.
Emmanuel Macron was elected president of France on Sunday with a business-friendly vision of European integration, defeating Marine Le Pen, a far-right nationalist who threatened to take France out of the European Union, early projections showed.
The centrist's emphatic victory, which also smashed the dominance of France's mainstream parties, will bring huge relief to European allies who had feared another populist upheaval to follow Britain's vote to quit the EU and Donald Trump's election as US president.
The Interior Ministry revealed that Macron had beaten Le Pen by around 66 percent to 34 - a gap wider than the 20 or so percentage points that pre-election surveys had pointed to.
It was a record performance for the National Front, a party whose anti-immigrant policies until recently made it a pariah in French politics, and underlined the scale of the divisions that Macron must now try to heal.
Le Pen's high-spending, anti-globalisation 'France-first' policies may have unnerved financial markets but they appealed to many poorer members of society against a background of high unemployment, social tensions and security concerns.
Macron's immediate challenge will be to secure a majority in next month's parliamentary election for En Marche! (Onwards!), his political movement that is barely a year old, in order to implement his programme.
"New page" for France
Macron, in a solemn televised victory speech, vowed to heal the social divisions exposed by France's acrimonious election campaign and bring "hope and renewed confidence" to the country.
"A new page in our long history is opening," he declared.
The 39-year-old former investment banker, who served for two years as economy minister but has never previously held elected office, will become France's youngest leader since Napoleon with a promise to transcend outdated left-right divisions.
At least one opinion poll published in the run-up to the second round has indicated that the majority he needs could be within reach.
Despite having served briefly as economy minister in President Francois Hollande's deeply unpopular Socialist government, Macron managed to portray himself as the man to recast a political landscape moulded by the left-right divisions of the last century.
While Macron sees France's way forward in boosting the competitiveness of an open economy, Le Pen wanted to shield French workers by closing borders, quitting the EU's common currency the euro, radically loosening the bloc and scrapping trade deals.
Socialist Prime Minister Bernard Cazeneuze said France had chosen to retain its place at the heart of Europe.
Le Pen Congratulates Macron
France's far-right National Front must be relaunched, Marine Le Pen said on Sunday after congratulating new French President Macron and conceding defeat to her rival in France's presidential election.
"The National Front ... must deeply renew itself in order to rise to the historic opportunity and meet the French people's expectations," Le Pen said in a brief address to supporters shortly after initial projections were released.
"I will propose to start this deep transformation of our movement in order to make a new political force," she added.
She also claimed Sunday's election was a "historic, massive result" for her party despite their defeat and claimed the mantle of France's main opposition. Le Pen called on "all patriots to join us" in constituting a "new political force."
Her deputy said this new force would not be called "National Front."
When he moves into the Elysee Palace after his inauguration next weekend, Macron will become the eighth - and youngest - president of France's Fifth Republic.
He plans to blend a big reduction in public spending and a relaxation of labour laws with greater investment in training.
A European integrationist and pro-NATO, he is orthodox in foreign and defence policy and shows no sign of wishing to change France's traditional alliances or re-shape its military and peace-keeping roles in the Middle East and Africa.
His election also represents a long-awaited generational change in French politics that have been dominated by the same faces for years.
He will be the youngest leader in the current Group of Seven (G7) major nations and has elicited comparisons with youthful leaders past and present, from Canadian Prime Minister Justin Trudeau to British ex-premier Tony Blair and even President John F. Kennedy in the United States.
US President Donald Trump congratulated Emmanuel Macron on winning the French presidency election and added he was looking forward to working with him.
"Congratulations to Emmanuel Macron on his big win today as the next President of France. I look very much forward to working with him!" Trump said on his official Twitter feed.
TRT World correspondent Simon McGregor-Wood has more from Paris.