He is a former Ultimate Fighting Championship (UFC) featherweight and lightweight double-champion.
As of 19 July 2021, he is ranked #9 in the UFC lightweight rankings.
In his debut professional boxing match, he was defeated by Floyd Mayweather Jr.
He is the biggest pay-per-view (PPV) draw in MMA history, having headlined five out of the six highest-selling UFC pay-per-view events.
His headline bout with Khabib Nurmagomedov at UFC 229 drew 2.4 million PPV buys, the most ever for an MMA event.
His boxing match with Mayweather drew 4.3 million PPV buys in North America, the second most in combat sports history.
McGregor was ranked as the world's highest paid athlete by Forbes in 2021, earning a reported $180 million.
He also featured in the list in 2018, when he was ranked fourth, with a reported income of $99 million.