One of the billionaire bosses of one of Australia’s most successful start-ups says he’ll give away half of his $7 billion fortune.

The Giving Pledge is a promise by the world’s wealthiest people to dedicate the majority of their wealth to charitable causes.

The couple has also joined the London-based non-profit organization, Founder’s Pledge, with a commitment to donate 25 percent of their fortune over the next five years.

“We are particularly fond of the structured method that the Founder’s Pledge employs in its philanthropy—it’s a constructive habit to incorporate into our standard practices,” he mentioned to the newspaper.

“The vast majority of our wealth is still embodied in Canva, so as it continues to grow so does our potential impact.

“We feel an immense responsibility to put the value of Canva back into serving our communities and the world.”

In the last few years, the couple has already donated “tens of millions” to support biodiversity causes and climate start-ups, the paper reported.

They are especially interested in environmental causes, and former zoologist Miller already runs “nature positive” financier, Wedgetail.

“Lisa’s experience as a zoologist and her tenure at the Australian Museum provide her with strong connections in this field. Her passion for animals and the environment has influenced me and our entire family,” Adams stated.

“Our focus really crystallised during the devastating 2019 east coast bushfires when we read that an estimated three billion animals died or were displaced,” he said.

“That was a pivotal moment for us to start putting our plans together, and it inspired Lisa to focus full-time on establishing Wedgetail and regenerative work.”

Adams is the Chief Product Officer of the company, which he started with Melanie Perkins and Cliff Obrecht.

It offers online design tools and was launched in 2013.

The other founders are also giving away much of their wealth via The Giving Pledge. Last year they handed out $19 million.