Indonesia's election commission on Monday announced the candidates for next year's presidential vote when the world's third largest democracy is due to pick a successor to incumbent leader Joko Widodo.

The February election will see three contenders vying for the Muslim-majority country's top office, with defence minister and former special forces general Prabowo Subianto battling former Central Java governor Ganjar Pranowo and former Jakarta governor Anies Baswedan.

Nearly 205 million people are eligible to vote on February 14, with the winner set to succeed Widodo after he completes the maximum two terms ruling Southeast Asia's biggest economy.

The country's General Elections Commission (KPU) said the three registered candidates were all confirmed for the vote after a series of eligibility and health screening checks, an announcement that marked the start of election season.

"Anies Baswedan and Muhaimin Iskandar, Ganjar Pranowo and Mahfud MD, Prabowo Subianto and Gibran Rakabuming Raka have been declared eligible as presidential and vice-presidential candidate pairs for the simultaneous elections in 2024," KPU commissioner Idham Holik told a press conference.

Subianto, 72, is increasing his margin of popularity over closest rival Pranowo, according to a poll published Sunday by Indikator Politik Indonesia.

The third-time presidential candidate is now favoured by 39.7 percent of voters to 30 percent for Pranowo, the poll showed, compared to 36.1 to 33.7 last month.

The vote has already been mired in controversy after a judicial panel dismissed the country's top judge Chief Justice Anwar Usman, who is Widodo's brother-in-law, after finding him guilty of an ethics violation over a ruling that allowed Widodo's son to run for vice president.

Gibran Rakabuming Raka, the 36-year-old mayor of Surakarta city, was allowed to become Subianto's running mate after Usman's ruling that changed the rules to allow candidates under 40 years of age to run if they have held a regional position.

Widodo's Indonesian Democratic Party of Struggle (PDI-P) has chosen Pranowo -- who was initially touted as the favourite -- as its candidate. He has picked chief security minister Mahfud as his running mate.

The third challenger Baswedan is favoured by conservative Muslims and Islamist groups. He chose Iskandar, the chairman of the Islamist National Awakening Party (PKB), as his running mate.

The official campaign period starts on November 28 but the presidential hopefuls have already embarked on nationwide tours seeking support from voters.

The next president will be sworn in next October, the elections commission said.