Now we're verrrrrrry skeptical of this for a number of reasons but it doesn't stop it being a terrifying watch. And as such it's got over 650k views in less than 24 hours.
Anyway, here's why we think it's a fake.
1: Who goes for your everyday swim with a GoPro attached to them? 2: Who, upon seeing a shark in the water, doesn't immediately start swimming for their lives to the shore? 3: This shark doesn't look like a Great White and it seems to swim into the very cliff the man jumps off. 4: The camera lense is wide-angle above the water but conveniently normal when looking at the shark. 5: If this happened to us, we'd probably just poo ourselves or have a heart attack and die immediately (in which case the video would not be shareable).
We could go on, but look, judge for yourself. It's still one of the biggest fears for most people on the planet so it's not even comfortable viewing if it is in fact fake. And if it's real this guy is hella lucky (although his bit to camera at the end is baloney).