The question of the world’s largest mountain does not have a single, simple answer, as the title depends entirely on how the measurement is defined. Geographers and geologists use different criteria to quantify a mountain’s size, leading to three distinct contenders for the title. The mountains that claim the top spot vary significantly based on whether one measures altitude above sea level, total vertical dimension from base to peak, or the physical distance from the Earth’s core. Exploring these different scientific metrics reveals the dynamic and complex nature of planetary geology.
Highest Point Above Sea Level
The definition most familiar to the public measures a mountain’s height from mean sea level (MSL), establishing the highest point on the planet’s surface. This standard is universally adopted because MSL provides a consistent, zero-elevation reference point across the Earth. The undisputed title for the highest mountain above this reference belongs to Mount Everest, known locally as Sagarmāthā in Nepal and Chomolungma in Tibet.
The peak sits in the Mahalangur Himal sub-range of the Himalayas, straddling the border between Nepal and the Tibet Autonomous Region of China. Following a joint survey completed in 2020, its official height was set at 8,848.86 meters (29,031.7 feet) above sea level. This measurement represents the snow height of the peak. Everest’s immense height is a result of the ongoing collision between the Indian-Australian and Eurasian tectonic plates, a process that continues to push the Himalayan range upward.
Tallest from Base to Peak
A different perspective on mountain size focuses on the total vertical rise from the mountain’s structural base to its summit, regardless of whether that base is above or below the ocean surface. This measurement captures the mountain’s complete geological mass and its true vertical dimension. By this metric, the Pacific Ocean’s Mauna Kea volcano on the island of Hawaiʻi holds the title as the world’s tallest mountain structure.
Mauna Kea is a dormant shield volcano, and the vast majority of its bulk is submerged beneath the waves of the Pacific Plate. Its peak reaches 4,207.3 meters (13,803 feet) above sea level, which is a significant height, though less than half the elevation of Everest. However, when measured from its base on the ocean floor, Mauna Kea’s total height is approximately 10,205 meters (33,481 feet), making it almost a mile taller than Mount Everest. This massive structure formed as the Pacific Plate moved over a stationary hot spot, causing repeated lava flows to build the mountain.
Farthest Point from Earth’s Center
The third, most technical definition of “largest” considers the mountain’s peak in relation to the center of the Earth, a geodesic measurement. This metric reveals the influence of the planet’s actual shape, which is not a perfect sphere but an oblate spheroid, meaning it bulges outward around the equator due to centrifugal force from the planet’s rotation. This equatorial bulge causes any point on the equator to be naturally farther from the center of the Earth than a point at a higher latitude.
Due to its location near the equator in Ecuador, the peak of Chimborazo, an inactive stratovolcano in the Andes, is the farthest point from the planet’s center. Chimborazo’s summit elevation above sea level is 6,263 meters (20,548 feet), which is considerably lower than Everest. However, its proximity to the equator means its peak is approximately 6,384.4 kilometers from the Earth’s center, a distance that is about 2.1 kilometers farther than the peak of Mount Everest.