The debate was a marathon, running into extra time to last three and a half hours and covering a wide range of subjects from security and secularism to the retirement age and working hours.
The TF1 television channel took the controversial decision to invite only five of the 11 candidates, excluding the six who are performing worst in the opinion polls.
Security, immigration, secularism
With questions on security, immigration and secularism dominating the opening section, Le Pen claimed that crime has "exploded", called for a ban on the Islamic
- Francois Fillon of the mainstream-right Republicans;
- Benoît Hamon of the Socialist Party;
- Marine le Pen of the far-right National Front (FN):
- Emmanuel Macron of the centrist En Marche! (Let's go!);
- Jean-Luc Mélenchon of the hard-left La France Insoumise (Defiant France).
headscarf in the street and in workplaces and said she wants to stop all immigration.
"I want to stop both illegal and legal immigration, with a limit of 10,000 for legal immigration," she said. "We must have national borders, because I don't know how we can count on a struggling Greece or a swamped Italy to control this enormous and uninterrupted flow."
Socialist Benoît Hamon praised German Chancellor Angela Merkel's decision to allow in refugees, pointing out that France has accepted a small percentage of those fleeing conflict in Syria, Iraq and other countries and calling for a "humanitarian visa".
Fillon claimed that most of the migrants now entering Europe are not fleeing war but poverty and called for quotas to be set by the French parliament
"You can always invent quotas, labels, whatever you want, until the day that someone comes looking for help," the hard left's Jean-Luc Mélenchon replied. "What are you going to do? Throw them into the sea?"
Macron waited until later to respond to Le Pen, goaded by her jibe that he had opposed banning the burkini swimsuit when the subject hit the headlines last summer.
“You are lying by twisting the truth,” he said, accusing the far-right candidate of “dividing” society.
Environment and climate change
On the environment and climate change, subjects that have received little attention during the campaign so far, Mélenchon and Le Pen had most to say.
The hard-left candidate called for an end to nuclear power, which provides the majority of France's electricity, promised a green economy with job-creation in renewables and chemical-free farming.
Hamon also called for the phasing out of nuclear power stations while Macron and Fillon defended them as a non-carbon source of energy.
Le Pen called for a buy national policy and protectionist policies to defend French farmers and businesses against "unfair" competition from eastern Europe and overseas.
Unemployment, living standards, the 35-hour week
Fillon and Macron advocated local and industry-wide negotiations on working hours, effectively encouraging the continued erosion of the 35-hour working week, while Hamon and Mélenchon called for shorter working hours.
There was a similar division on retirement age, which the right and centre wish to push up, and on how to improve the economy - the left calling for boosting demand with higher wages, the right with tax cuts for business and individuals.
Hamon's defence of his proposal of a universal basic income has been widely judged less than spirited, despite goading from Fillon who claimed it would push France deeper into debt.
Calling for "economic patriotism", Le Pen showcased her party's revamped social programme, calling for savings to be made elsewhere instead of raising the retirement age, advocating increased disability benefits and defending a public health insurance.
With Hamon and Mélenchon lukewarm on Europe, it fell to Macron and Fillon to defend the EU against Le Pen.
She wants France to leave the euro and a referendum on EU membership.
Leaving the eurozone would hit consumers' spending power hard, Fillon argued, while Macron derided her for praising Britain's decision to quit the EU.
"All the people who wanted Brexit have chickened out and have not wanted to take power," he said, calling for a "strong France in a strong Europe".
Le Pen and Fillon talked tough on terror, the FN candidate calling for Islamist organisations to be banned, borders to be closed, strip terrorists of French nationality and deport foreigners on terror watchlists, Fillon predicting a long war with "Islamist totalitarianism" and calling for "those who take up arms against France" to be deprived of their nationality.
Macron called for international cooperation against terrorism, prison for people who have joined armed jihadi groups abroad and a "diplomatic solution" in Syria and Iraq.
"To say that a change of government would mean there would be no more terrorism would be absurd," Hamon commented. He called for and end to closer relations with Qatar and the UAE and an increase in development aid, while opposing stripping offenders of their French citizenship.
"Today terrorist acts are essentially the work of political Islamism, which is fighting for access to resources - gas, oil - religion is a pretext," Mélenchon declared. Companies, like cement-maker Lafarge, that "collaborate with the enemy" should be punished, he said.
To read our coverage of the French presidential election campaign click here
Two more debates will be televised.
The first round of presidential elections are set for 23 April, the deciding round on 7 May.