Ana Elizarraras had last been seen in a car with three males near Vineyard Avenue and First Street in Pleasanton around 4 p.m. Sunday, police said.
Ana had apparently willingly left her home Sunday morning, but did not get in touch with family or friends after she left, prompting the search, police said.
She was found around 11 a.m. in San Jose by a family member, Pleasanton police Detective Eric Gora said.
She is back home in Pleasanton, "safe and with family," Gora said.
Ana was considered at-risk because of her young age, according to police.