I assume you must live a VERY spartan life in the Bay. Basically pay your rent (which must be shared or very cheap for the Bay) and utilities and not do much else...
I mean the average Bay area rent is more than the difference between your take home and your savings...
edit: I'm using ADP's calculator, don't know why SmartAsset is different but ADP is pretty legit so I'm going to continue to lean towards those numbers.