New Zealand golfer Ryan Fox is still processing his "life-changing" win at the British Open after sinking a birdie putt on the 18th hole and securing victory.

Fox won the Open Championship at Royal Birkdale on Monday by one stroke, joining Sir Bob Charles - who won the Open in 1963, Michael Campbell and Dame Lydia Ko as the only New Zealanders to have won a golf major.

After a whirlwind 24 hours, Fox told RNZ's Checkpoint programme today he was just about ready to crash.

"I'm still buzzing. When my head hits the pillow I'll still be going through the ramifications of what's happened and trying to figure out how it happened and everything like that, it's pretty surreal."

Fox is only the second Kiwi to win the men's Open Championship and said the result was going to be life-changing.

"It's a piece of sporting history, I think, really. In golf, winning a major is a huge thing, and I think in terms of New Zealand, we haven't had many of them."

He said he expected it would open doors for him and New Zealand going forward.

"In some ways it'll make life a lot easier, I'll be able to pick and choose my schedule a bit more, know what events I'm going to be in a lot longer in advance than what it's been the last couple of years in the US.

"But also life's going to get a whole lot busier, there'll be a lot more scrutiny, a lot more eyeballs on, especially over here in the US."

The win sees Fox climb from 56th to 22nd in the world rankings.

"It's more than a dream come true. I don't quite know what to think of it yet, like it's so big and it all happened so fast. I kind of haven't had a chance just to kind of sit down and reflect."

Aside from a few shots on social media, Fox said he had not seen anything of his win yet, so planned to sit down in front of the TV and rewatch the moment in the hopes of it finally soaking in.

Ryan Fox celebrates after he holes his putt on the 18th green at Royal Birkdale Golf Club. Photo: Reuters

Fox told Checkpoint the win probably stemmed from a theory he had been following on the course all week.

"I was aggressive, I like to play that way anyway. I got to the tee on 18 and said to my caddy, 'Well, I'm going to try to win this…' If I pulled it off, I gave myself a chance. If I didn't, well, I was ready to live with the consequences of that."

It was a relief to make that call and have it pay off.

"If it didn't happen, I was okay with that, and I know I would have been more annoyed at myself if I'd have tried to lay up and play conservative and then made a bogey from there and missed out on the playoff."

Fox said the feeling when hitting the putt on Monday was like nothing he had ever experienced.

"I've had putts to win tournaments before, but my hands have never been shaking that much.

"I had to kind of step away, take a couple of deep breaths and just go, 'Okay, well, it's just a putt, you know? Pick a line, hit it and hope it goes in' - and thankfully it did."

After a whirlwind of celebrations Fox boarded a flight back to Florida to see his family, which he took on with little sleep.

While he hadn't had the time to figure out how he was going to reward himself, he expected it may involve a few nice bottles of wine.

"Normally, I am one of those people that like to treat myself to something as a little reward. So I'm sure over the next few weeks I'll get a chance to think of that.

"I'll probably find myself a couple of really, really nice bottles of wine to drink with friends and family when we get back to New Zealand at some point."