A New Zealand man whose ambitious crowdfunding campaign raised millions of dollars to buy a pristine South Island beach and make it public parkland said on Monday it was "surreal" to see his dream realized.

Duane Major's push earlier this year to take Awaroa beach out of private hands and make it a national park quickly went viral, attracting 40,000 donations to raise a total of NZ$2.3 million (US$1.7 million).

Major, a pastor who describes himself as "an ordinary bloke", was present when the beach was officially incorporated into the Abel Tasman National Park at a Maori ceremony on Sunday.

"I must say, it might have been the wind, but I might have squeezed out a wee tear or two," Major told TV3 on Monday.

Awaroa inlet is an 800-meter stretch of golden sand at the top of South Island.

Accessible only by boat or helicopter, it came on the market late last year, with real estate agents marketing it as "the best beach on the planet".

Major decided after discussions with relatives over the Christmas period to set up the crowdfunding page.

"We just gave it shot," he said.

"We didn't know how it would pan out and the magical experience it's been, it was kind of surreal."

It was the largest crowdfunding effort ever facilitated by website Givealittle, with donations ranging from children pledging a dollar to corporations giving tens of thousands.

The government chipped in NZ$350,000 and Associate Conservation Minister Nicky Wagner said future generations of New Zealanders would now enjoy it.

"It's a victory for positive people power and for preserving our environment," she said.