Silao is located at . It has an average elevation of 60 metres (196 feet).
India census, Silao had a population of 20,177. Males constitute 52% of the population and females 48%. Silao has an average literacy rate of 52%, lower than the national average of 59.5%: male literacy is 60%, and female literacy is 43%. In Silao, 19% of the population is under 6 years of age.