Topanga, CA has a population of 7,858 and is the 4,766th largest city in the United States. The population density is 411 per sq mi which is 77% higher than the California average and 353% higher than the national average. The median age in Topanga is 48 which is approximately 33% higher than the California average of 36. In Topanga, 61% of the population over 15 years of age are married, 81% speak English and 4% speak Spanish. 42% of Topanga residents were born in California, 35% were born out of state, 4% were born outside of the United States and 19% were foreign born.