It's taken Wozniacki 11 years, 43 majors, 256 tournaments, 772 matches and untold hours of toil and tears to shed her tag as tennis's most accomplished talent without a grand slam win.
Herself a two-time grand slam runner-up, on the Paris clay in 2014 and 2017, Halep made a nervy start to the finale.
Playing in sapping heat and humidity, Halep dropped serve with an overcooked backhand in the second game of the match as Wozniacki powered to a 3-0 lead.
But, after looking in control, Wozniacki's first display of tension came with the second seed serving for the opening set at 5-3.
Distracted by an overzealous fan in Rod Laver Arena, Wozniacki urged the chair umpire to intervene.
The rattled Dane promptly dropped serve for the first time, before regaining her cool to dominate the tiebreaker to pocket the opening set in 50 minutes.
Halep, who carried an ankle injury throughout her gruelling two-week campaign, called for the tournament physio while leading 3-2 in the second set.
The hobbling top seed resumed after having her pulse and blood pressure checked and bravely snatched the second set after reeling off three straight games to set up a thrilling conclusion.
But it was Wozniacki who finally prevailed, emerging from a 10-minute break allowed under the Open's heat rule to claim the rollercoaster third set featuring seven services breaks.