San Bruno, CA has a population of 42,736 and is the 959th largest city in the United States. The population density is 7,807 per sq mi which is 3259% higher than the California average and 8516% higher than the national average. The median age in San Bruno is 39 which is approximately 9% higher than the California average of 36. In San Bruno, 56% of the population over 15 years of age are married, 50% speak English and 21% speak Spanish. 52% of San Bruno residents were born in California, 11% were born out of state, 3% were born outside of the United States and 35% were foreign born.