The athlete earned more than $ 250 million in one year.
Former five-division world champion Floyd Mayweather Jr.
American boxer Floyd Mayweather is on top of the list with 285 million dollars in pretax annual earnings.
George Clooney finishes second with $239 million, most of it coming from liquor giant Diageo's purchase of Casamigos, the tequila company he cofounded, giving him the best annual take-home of his-or any actor's-career.
McGregor made an estimated $85 million for his professional boxing debut against Floyd Mayweather Jr. past year with his opponent taking the number one spot on the list with an estimated earnings of $275 million. Numerous highest earners came from celebrities leveraging on their brands through side ventures and their social media presence.More news: Google introduces new job search feature for United Kingdom workers
More news: Surprise stall for inflation raises questions over interest rate hike
More news: ‘Glass’ Trailer Teaser Offers a Taste of M. Night Shyamalan’s ‘Unbreakable’ Sequel
"Entertainers have found all sorts of new ways to monetise their audiences, especially with the help of social media".
20-year-old Jenner recently attracted headlines for being within reach of becoming the world's youngest self-made billionaire, as Forbes estimated her net worth to be $900 million earlier this month. According to the Forbes earnings of the "Jumanji" and "Fast & Furious" star were the largest acting-related earnings it had recorded in 20 years.
The top earner on last year's list, musician Sean Diddy Combs, dropped to No. 32 on the current list.
Also in the top ten most richest celebrities of the year included lawyer and TV presenter Judith Sheindlin, wrestler and actor Dwayne Johnson, the Irish rock band U2, the British band Coldplay, the Argentine striker Lionel Messi and Portuguese player Cristiano Ronaldo and British pop singer ed Sheeran, who became the highest-paid solo musician in Forbes.
"The list is 85% men - who earned a combined $5.3 billion to the women's $1.05 billion", the list reads.