The tallest mountain from base to summit. Using that measurement, Denali is taller than Mount Everest. Denali rises about 18,000 feet (5,500 meters) from its base, which is a greater vertical rise than Everest's 12,000-foot rise (3,700 meters) from its base at 17,000 feet (5,200 meters). But Denali and Everest are both dwarfed by Mauna Kea in Hawaii. When measured from the ocean floor to its summit, that mountain is 33,476 feet (10,204 meters) tall. However, only 13,803 feet (4,207 meters) rise above sea level.