Rainbow, CA has a population of 1,780 and is the 11,708th largest city in the United States. The population density is 161 per sq mi which is 31% lower than the California average and 78% higher than the national average. The median age in Rainbow is 50 which is approximately 39% higher than the California average of 36. In Rainbow, 60% of the population over 15 years of age are married, 68% speak English and 25% speak Spanish. 50% of Rainbow residents were born in California, 28% were born out of state, 1% were born outside of the United States and 20% were foreign born.