Hayward, CA has a population of 154,507 and is the 165th largest city in the United States. The population density is 3,393 per sq mi which is 1360% higher than the California average and 3645% higher than the national average. The median age in Hayward is 35 which is approximately 4% lower than the California average of 36. In Hayward, 52% of the population over 15 years of age are married, 42% speak English and 32% speak Spanish. 50% of Hayward residents were born in California, 9% were born out of state, 2% were born outside of the United States and 39% were foreign born.