Stone's pretax income largely came from her role in La La Land, which grossed $445.3 million at the global box office, as well as earning her a Best Actress Oscar.
Forbes editor Natalie Robehmed told ET that the publication believes Stone "took a lower upfront pay in order to get more compensation on the back end. The movie went on to do phenomenally well."
Jennifer Aniston is the second highest-paid actress, earning $25.5 million. While some may be surprised to find Aniston at No. 2 on this year's list, Robehmed explained that the 48-year-old star "still makes millions from endorsements for Smart Water and Aveeno."
Jennifer Lawrence jumped from being No. 1 on the list for the past two years, to being No. 3 this year, bringing in $24 million. Without the Hunger Games franchise, most of the 27-year-old's income came from her upcoming movies Mother! and Red Sparrow and endorsement with Dior.
Melissa McCarthy ($18 million) and Mila Kunis ($15.5 million) round out the top five.
According to Forbes, the world's 10 highest-paid actresses tallied a combined $172.5 million between June 1, 2016, and June 1, 2017, before fees and taxes.
"We rank our highest-paid actresses list by looking at upfront fees and back-end profits for movies," Robehmed told ET. "As well as endorsement paychecks and any other earnings that the actresses might have gotten within our 12-month scoring period, which is from June 2016 to June 2017. All our estimates are before taxes and fees."