Vowing to reverse the legacy of right-wing President Nicolas Sarkozy, Hollande promised €20 billion ($26 billion) in new spending by 2017, the creation of 60,000 new teaching jobs and 150,000 new jobs for young workers.
He promised to have a balanced budget by 2017 and vowed to cancel about €29 billion in tax breaks, including €17 billion in breaks for big business.
"I only make promises that I will be able to keep, nothing more, nothing less. Everything I say will be done," Hollande said as he presented the programme before 400 journalists and party loyalists at a union hall.
His goal, he said, "is to ensure that the French people can again believe in the future."
The wide-ranging programme focused heavily on traditional Socialist values, from state-funded job creation to boosting taxes on the rich.
Accusing Sarkozy of granting €75 billion in "fiscal gifts" to France's richest, Hollande vowed to "protect the middle class".
He promised a significant reform of the tax system aimed at increasing taxes on the wealthy, including a new higher rate of 45 percent for incomes above €150,000 per year.
He vowed a 15 percent increase on taxes on bank profits and said he would focus on improving the climate for small businesses by creating a public fund to assist them.
Among the jobs to be created, he said, would be a 1,000 new public-sector jobs every year in the police and justice system.
Hollande also promised to cut by 30 percent the salaries of the president and government ministers and to introduce a form of proportional representation for parliamentary elections.
He made pledges too on increases in social housing, development plans for depressed suburban areas, granting marriage and adoption rights to homosexual couples and a reduction in France's dependence on nuclear power from the current 75 percent to 50 percent by 2025.
On the international front, Hollande promised to immediately withdraw French troops from Afghanistan and proposed a new "responsibility, governance and growth pact" to address the eurozone economic crisis.
Sarkozy's allies were quick to denounce the programme, with government spokeswoman Valérie Pécresse accusing Hollande of making irresponsible promises that would worsen public finances.
"This is a project that threatens the social model, France's credibility and the French people," said Pécresse, who is also budget minister.
"All of this is not serious, it would put France in the red. The budget deficit would continue to grow, the debt would continue to grow. There would then be no other solution than increasing taxes on the middle class."
Hollande has consistently led opinion polls with 28-30 percent of votes predicted in the first round on April 22, ahead of 23-24 percent for Sarkozy, who has yet to officialy declare his candidacy.
Polls suggest that far-right leader Marine Le Pen of the National Front would garner 18-20 percent of votes and centrist candidate Francois Bayrou 12-14 percent -- but their numbers are on the rise, at the expense of both Sarkozy and Hollande.
Hollande's other opponents also slammed his programme.
"We will never return to a (budget) balance with this programme. It is not truthful, it is not imaginable. There is not a single measure for the economy in this programme," Bayrou told Radio Classique.
On France Info radio, Le Pen called Hollande's programme "a sanitised project" that is nothing more than "a version of the model... that is at the origin of the (economic) crisis."
Analysts say Sarkozy is especially vulnerable on the economy, which has suffered from France's exposure to the eurozone debt crisis and which some predict will enter a brief recession early this year.