* Highest above sea level: Mount Everest is the highest mountain on Earth, with a summit elevation of 8,848.86 meters (29,031.7 feet).

* Highest from base to peak: Mauna Kea, a dormant volcano in Hawaii, is the largest mountain from base to peak, measuring approximately 10,203 meters (33,474 feet) from its base on the ocean floor to its summit.

* Highest based on total volume: Mount Denali (formerly Mount McKinley) in Alaska, is the highest mountain in North America and the tallest mountain on Earth when measured from its base at the sea level to its summit.

So, the answer depends on what criteria you use to measure "biggest". 😊