Social media stars and sporting champions are splashing the cash for Australian bushfire relief efforts and urging fans to do the same.

Twenty-six people have died since the start of the disaster in September, more than 2,000 homes have been destroyed, and some eight million hectares (80,000 square kilometres) has burned -- an area roughly the size of Ireland or South Carolina.

 Aussie A-listers donate 

Australian Marvel actor Chris Hemsworth said he would donate AUS$1 million, singers Kylie and Danni Minogue pledged AUS$500,000 to the country´s rural firefighters, a donation matched by Nicole Kidman and her husband Keith Urban.

Compatriots including Russell Crowe -- who used his Golden Globe win to speak about the tragedy -- and Rebel Wilson have pledged donations, with singer Dami Im also donating.

 Serena plays for charity 

Athletes like Lewis Hamilton, tennis players Ashleigh Barty, Maria Sharapova and Novak Djokovic, and cricketers -- including Chris Lynn and Glenn Maxwell -- offered to donate their winnings.

On Wednesday, organisers of the Australian Open said Roger Federer, Serena Williams and Rafael Nadal will headline a charity match ahead of the tournament.

 $1m for ´baggy green´

Many celebrities will auction clothes: Williams is donating a signed dress, while British actor and writer Phoebe Waller-Bridge announced her Golden Globes suit would be auctioned off, and Shane Warne sold his baggy green cap to an anonymous bidder for AUS$1 million.

 Kylie contributes 

American stars -- including Kylie Jenner, singers Pink, Lizzo, and Shawn Mendes, talkshow host Ellen DeGeneres, and actor Patricia Arquette -- all pledged to contribute to relief efforts.

Leonardo DiCaprio´s environmental group, Earth Alliance, also said it was giving US$3 million.

 Rocket Man 

Elton John announced during a performance on Tuesday he would donate $1 million, and Metallica said they would give $500,000 to the county´s fire service.

Celebrities such as Margot Robbie, Naomi Watts, Hugh Jackman, and Selena Gomez also announced they had donated but declined to state how much.