Here's a sectional with overlays showing the relatively new (August 2018) Class B airspace around SFO.
Blue is the new definition and Yellow the old one.
They tweaked it mostly to allow better flow to SJC, San Carlos (SQL), Palo Alto (PAO), and Moffett Field (NUQ) without compromising SFO traffic.
This may give you a better idea of what the airspace actually looks like, especially if you're unfamiliar with reading a sectional chart.
As you can see, it's a lot like an inverted wedding cake.
Hope this helps.
- Plat