Jeff Bezos' wealth crosses $80 billion mark

Bezos is within striking distance of Microsoft's Bill Gates

Jeff Bezos' net worth just passed $80 billion, putting him within $5 billion of becoming the world's richest man.

According to the Bloomberg Billionaire's Index, the surge in Amazon's share price overnight added $3.3 billion to his fortune. That puts the Amazon founder's net worth at just over $82 billion. He's now within striking distance of Bill Gates, whose wealth Bloomberg lists at $87 billion.

With Microsoft shares poised to open virtually flat, Bezos could become the richest man even sooner.

Bezos has added $65 billion to his net worth over the past five years, according to Bloomberg.

Even if Gates' wealth holds steady, Amazon stock only needs to hit $990 — up from $947 Friday — for Bezos to become number one.