Berkeley is served by BART (Bay Area Rapid Transit) with three stations: Downtown Berkeley, North Berkeley, and Ashby. From San Francisco, the ride to Downtown Berkeley takes about 25 minutes. From Oakland, it is about 10 minutes. BART is the obvious choice from the airport or from anywhere in the Bay Area with rail access.
By car, Berkeley is off I-80 and accessible from the Bay Bridge. Parking near the campus is difficult and expensive; the BART stations have garages if you're driving from the East Bay suburbs.
From San Francisco International Airport (SFO), BART runs directly to Berkeley with no transfers. From Oakland Airport (OAK), take the BART connection from the airport.