The Mariana Trench is about 36,000 feet deep , with the deepest reliably measured point (Challenger Deep) at roughly 36,037–36,070 feet below sea level.

Quick depth facts

  • Most modern measurements put Challenger Deep near 36,070 feet (10,994 meters).
  • Earlier and alternative surveys report values in the same ballpark, around 35,840–36,201 feet , reflecting small differences in methods and conditions.

Why the exact number varies

  • Different expeditions use various instruments (sonar vs. pressure sensors), which leads to slightly different depth readings of a few dozen to a few hundred feet.
  • Because of that, sources often round it and simply say the Mariana Trench is “almost 7 miles deep,” which is just under 36,200 feet.

In everyday terms: saying the Mariana Trench is about 36,000 feet deep is accurate enough for general use, while scientific discussions often quote specific measurements like 36,070 feet.

TL;DR: The deepest part of the Mariana Trench, Challenger Deep, is roughly 36,000–36,100 feet below sea level.

Information gathered from public forums or data available on the internet and portrayed here.