Question

How long could an average human hold their breath underwater? Is there a difference between holding your breath above and below water level?

Answer 1

Two minutes is the average and most reasonable time that a human can use in order to breathe long under the water. As per experiences, and according to some experts, there is no notable difference between breathing above and under the water, and it's more related to psychological matters only.

Answer 2

An average human can hold their breath for about.. Maybe 15-30 seconds?
If you're stressed/panicked while holding your breath underwater, your hold time would be shorter, but if you're calm, it'll be much longer.
There is a difference between holding your breath above and below water level because we seem to hold our breath longer when we're not underwater.