Two Australians have paddled themselves into the record books by successfully completing the first kayak crossing of the Tasman.

James Castrission and Justin Jones received a heroes' welcome in the North Island port city of New Plymouth this morning.

The two young adventurers stood in the seats of their nine-metre kayak to salute the massive crowd of well-wishers that turned out on the New Plymouth foreshore.

They completed their epic paddle just after midday local time (10:00am AEDT), 61 days after setting out from Forster on the New South Wales mid-north coast.

They completed the last few kilometres flanked by a huge flotilla of fellow kayakers, pleasure craft and two Maori war canoes, ahead of a triumphant reunion with family and friends on the beach.

Although a little unsteady on their feet, the pair seemed in remarkably good physical shape after two months in the cramped confines of the kayak, but have been taken to hospital for precautionary checks.

They have promised to party hard to celebrate their record-breaking accomplishment as soon as they get the all-clear from doctors.

Mr Castrission thanked supporters: "Thank you so much guys, we're just going to go off to hospital now to get a check up, but we're so, so happy."

But it has not been plain sailing, with the wild stretch of water testing the two young adventurers' mettle, their kayak, and its equipment to the limit.

They had hoped to reach New Zealand by Christmas, but unhelpful headwinds and swirling currents out in the Tasman added an extra 1,000 kilometres to the journey and saw their food supplies dwindle.

In the end, conditions for their arrival off the Taranaki coast were benign.

In February last year another Australian, Andrew McAuley, went missing while attempting a solo kayak crossing of the Tasman.

His capsized kayak was found floating off the New Zealand coast near Milford Sound. He is presumed to be dead.