Location in Jharkhand, India
|Elevation||183 m (600 ft)|
|• Official||Hindi, Santali|
|Time zone||UTC+5:30 (IST)|
Sini is located at  It has an average elevation of 183 metres (600 feet). The main source of livelihood for the common people is the Railway Workshop situated near the Sini Railway Station. There is also one Zonal Training Centre of Indian Railways situated at Sini. There is a very famous railway park at the railway station. Sini is also blessed to have a very old cricket ground, popular as "Shershah Ground" (South Eastern Railway Sports Association or S.E.R.S.A.) where many inter division level competitions are held on a regular basis. Sini has NSCS Computer Education which is the only institute providing basic education of Computer since last 9 years. There is a famous school named S.E.RLY.INTER.COLLEGE up-to class 12th.This year(2013) in the matric examination 6 students of this school got more than 80percentile marks from JAC board and two of the students got rank in the district top 10..
As of 2001 India census, Sini had a population of 6,489. Males constitute 53% of the population and females 47%. Sini has an average literacy rate of 72%, higher than the national average of 59.5%: male literacy is 80%, and female literacy is 63%. In Sini, 12% of the population is under 6 years of age.