July 2018 has lowest summer fares I recall in more than a decade for travel from San Jose to Europe. The destinations change week to week and different alliances discount different cities. This week United Airlines has Copenhagen on sale as low as $531 round trip, Rome around $600 and Paris at $625. Most cities around Europe are priced over $800.
These are prices for July departures, typically the most expensive tickets to Europe besides Christmas season. If you can travel to Europe in mid-August or September, then ticket prices are widely available to many more cities in low $500s and even $400s.
London shows ticket prices around $600 round trip through Virgin Atlantic flights, but these are not pricing with direct links on Google Flights. Same issue with American Airlines to Rome with no direct booking link on Google Flights. Momondo.com might pull up these fares.
United Airlines San Jose SJC – Newark EWR – Hamburg HAM – Copenhagen CPH – Frankfurt FRA – San Jose SJC
Lufthansa Airlines San Jose SJC – Frankfurt FRA – Rome FCO – Frankfurt FRA – San Jose SJC
Lufthansa Airlines San Jose SJC – Newark EWR – Paris CDG – Frankfurt FRA – San Jose SJC