Mauna Kea is about 4.2 km above sea level — but nearly 10.2 km from ocean-floor base to summit.

Summit elevation is measured upward from mean sea level: about 4,207 m. Base-to-summit height is measured from the mountain's base on the ocean floor: approximately 10,211 m — nearly 10.2 km. Most of Mauna Kea is underwater, so the datum you pick changes the answer by more than the height of the visible mountain. We keep both as separate measurements rather than collapsing them into a single "true height", because each answers a different question.

Depends on the measurement reference — summit elevation and ocean-floor base-to-summit are distinct measurements, both valid.

These are two different measurements of the same mountain and are kept as separate properties: summit elevation is measured from sea level, base-to-summit from the ocean floor.

• Mauna Kea — USGS

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• Stack it up🪙About 1,045.
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