Sipsipin is a barangay in the municipality of Jalajala, in the province of Rizal. Its population as determined by the 2015 Census was 4,926. This represented 15.27% of the total population of Jalajala.

According to the 2015 Census, the age group with the highest population in Sipsipin is 5 to 9, with 562 individuals. Conversely, the age group with the lowest population is 75 to 79, with 26 individuals.

Combining age groups together, those aged 14 and below, consisting of the the young dependent population which include infants/babies, children and young adolescents/teenagers, make up an aggregate of 33.80% (1,665). Those aged 15 up to 64, roughly, the economically active population and actual or potential members of the work force, constitute a total of 62.61% (3,084). Finally, old dependent population consisting of the senior citizens, those aged 65 and over, total 3.59% (177) in all.   

The computed Age Dependency Ratios mean that among the population of Sipsipin, there are 54 youth dependents to every 100 of the working age population; there are 6 aged/senior citizens to every 100 of the working population; and overall, there are 60 dependents (young and old-age) to every 100 of the working population.   

The median age of 23 indicates that half of the entire population of Sipsipin are aged less than 23 and the other half are over the age of 23.

The population of Sipsipin grew from 2,082 in 1990 to 4,926 in 2015, an increase of 2,844 people. The latest census figures in 2015 denote a positive growth rate of 1.81%, or an increase of 443 people, from the previous population of 4,483 in 2010.

Sipsipin is situated at approximately 14.3720, 121.3377, in the island of Luzon. Elevation at these coordinates is estimated at 44.4 meters or 145.7 feet above mean sea level.