What is the tallest mountain in the world?

Nepal and China jointly announced the 8,849 m figure in December 2020, after a fresh survey using GPS and satellite data reconciled earlier Chinese and Nepali measurements that had differed by about 4 meters.

"Tallest" depends on how you measure

• Highest above sea level: Mount Everest (8,849 m) — the standard answer to this question.
• Tallest base-to-peak: Mauna Kea in Hawaii, which rises about 10,210 m from the ocean floor, though only about 4,207 m is above sea level.
• Farthest from Earth's center: Mount Chimborazo in Ecuador, because Earth bulges at the equator and Chimborazo sits close to it.

Everest sits in the Mahalangur Himal sub-range of the Himalayas and was first summited by Sir Edmund Hillary and Tenzing Norgay on 29 May 1953.