Kayaker Bonnie Hancock has paddled her way into Australian sporting history, claiming two world records after a gruelling 254-day journey at sea.

The 32-year-old set a record for the fastest circumnavigation of mainland Australia by paddle and the longest 24-hour paddle.

She battled crocodiles, sharks, hypothermia and waves as high as six metres before completing the 12,700-kilometre voyage on Sunday in waters off the Gold Coast.

Her achievements will be assessed by the Guinness World Records.

Bonnie Hancock arriving home on the Gold Coast this morning after her world record-breaking eight-month circumnavigation of Australia in a surf ski. Our chat tonight on @9NewsQueensland pic.twitter.com/K65PbO3RRl

— Abbey Geran (@AbbeyGeran) August 28, 2022

‘‘This 254-day journey has been life changing,’’ she said in a statement on Sunday.

‘‘(It) has been far tougher, but also far more incredible, that I could have ever imagined.

‘‘The first month, my back felt like breaking every day, but I knew the only way was forward. I knew my body was going to become conditioned to the extremes.

‘‘My will to complete this outweighed any pain.’’

Congratulations Bonnie Hancock on being the first Australian woman and youngest person to circumnavigate #TheGreatSouthernLand by surf ski. Fighting off crocs, great white sharks and freak waves stuff of legend! @minerva_network @Gotcha_4_Life #WomeninSport pic.twitter.com/SkoZkeslDu

— Professor Sarah Kelly OAM (@skelly8888) August 27, 2022

The ironwoman and dietitian started paddling in December and is the fifth person to complete the journey by ski or kayak.

The Ironwoman has so far raised $70,000 for mental health charity Gotcha 4 Life.

“The goal to do the fastest circumnavigation became my secondary focus as I went on,” she said.

“Gotcha4Life and raising money for mental fitness really gave me the motivation to continue.”

Highlights include paddling with dolphins off Port Lincoln, exploring caves surrounded by seals and coming close to a humpback whale and her calf.

She also experienced some incredible lows. She endured non-stop sea sickness during a gruelling 17 day passage across the Great Australian Bight which ended with her being treated in hospital for dehydration and exhaustion.

She was followed by a film crew who also provided food, medical help and kept her motivated.

-AAP