"Absolutely amazing," said Keys. "I served pretty well and I think I returned pretty well.
"So off of the first ball I had a bit of advantage on a lot of the points and then was able to dictate.
"I was going to have to take my chances and go for it because if I gave her an inch she was going to take it."
Both players, among the tour's biggest ball-strikers, have been in fine early season form.
Last weekend, Keys picked up the Adelaide International title while Badosa upset Krejcikova to win the Sydney Classic.
But Keys, who beat 2020 champion Sofia Kenin in the first round, was dominant.
She was exceptional in the opening set with Badosa having few answers to her consistent returns and strong serves.
Keys broke the Spaniard's first service game and gave Badosa little chance to strike back, slamming down serves at 188 kph (116 mph) and winning more than 80 percent of her first serve points.
She closed out the set with 16 winners to her opponent's four.
Badosa started taking more risks in the second set and landed some perfect returns to put pressure on the Keys serve.
They exchanged breaks before Keys' consistency and precision saw her break three more times to wipe the Spaniard off court.
The 2017 US Open finalist has played some of her best tennis in Australia, making the semi-finals 2015 and the quarters three years later with a sparkling 24-8 career record at Melbourne Park.