San Lorenzo, CA has a population of 24,790 and is the 1,754th largest city in the United States. The population density is 8,932 per sq mi which is 3744% higher than the California average and 9759% higher than the national average. The median age in San Lorenzo is 40 which is approximately 12% higher than the California average of 36. In San Lorenzo, 60% of the population over 15 years of age are married, 52% speak English and 25% speak Spanish. 57% of San Lorenzo residents were born in California, 9% were born out of state, 2% were born outside of the United States and 32% were foreign born.