San Jose Bike Party is a monthly social bicycle ride event in and around San Jose, California held on the third Friday of every month. Attendance varies with weather and time of year, usually ranging from hundreds in the winter months to low thousands in the summer. Established in 2007, it is the original 'bike party' now replicated in other cities around the world. Its motto is "Building community through cycling".

Critical Mass is a form of direct action in which people travel as a group on bicycles at a set location and time. The idea is for people to group together to make it safe for each other to ride bicycles through their streets, based on the old adage: there's safety in numbers.