The tallest mountain in the world depends on how “tallest” is defined, but the highest peak above sea level is Mount Everest, while the tallest from base to summit is Mauna Kea.

Quick Scoop

  • Mount Everest is the highest mountain above sea level , with a summit elevation of about 8,848.86 meters (29,031 feet).
  • Mauna Kea in Hawaii is the tallest mountain base to peak , rising about 10,205 meters (33,480 feet) from its underwater base, though only about 4,205 meters are above sea level.
  • In everyday use, when people say “tallest mountain in the world,” they almost always mean Everest, because height is usually measured from sea level rather than from the seafloor or Earth’s core.

Everest vs Mauna Kea

Here is a compact view of the two key contenders:

Mountain What it “wins” Height criterion Approx. height Location
Mount Everest Highest above sea level Sea level to summit 8,848.86 m (29,031 ft) Nepal / China (Tibet)
Mauna Kea Tallest base to summit Seafloor base to summit ≈10,205 m (33,480 ft) Hawaii, United States
[1][7] Information gathered from public forums or data available on the internet and portrayed here.