|Elevation||6 m (20 ft)|
|Time zone||IST (UTC+5:30)|
Kayalpattinam is located at  It has an average elevation of 6 metres (19 feet)..
According to 2011 census, Kayalpattinam had a population of 40,588 with a sex-ratio of 1,082 females for every 1,000 males, much above the national average of 929. A total of 4,995 were under the age of six, constituting 2,548 males and 2,447 females. Scheduled Castes and Scheduled Tribes accounted for 7.37% and .01% of the population respectively. The average literacy of the town was 81.3%, compared to the national average of 72.99%. The town had a total of : 9417 households. There were a total of 11,414 workers, comprising 17 cultivators, 27 main agricultural labourers, 206 in house hold industries, 10,717 other workers, 447 marginal workers, 9 marginal cultivators, 4 marginal agricultural labourers, 30 marginal workers in household industries and 404 other marginal workers.
Most of Muslims here follow Shafiee school and Faasiyatush shadhiliya Tariqa (Shadhiliyya Sufi order). Headquarters of this tariqa in Tamil Nadu zawiyatul fassiyatush shadhiliya is located here. There are followers of Qadiriyya Sufi order connected to Mahlara and a few wahabis.Maqbara of Hazrat Kazi Syed Alauddin brother of Hazrat Kazi Syed Tajuddin the fore father of Madurai Maqbara Hazrats' and of all the Syeds living in Kazimar Street, Madurai is located here.
- Falling Rain Genomics, Inc - Kayalpattinam
- "Census Info 2011 Final population totals". Office of The Registrar General and Census Commissioner, Ministry of Home Affairs, Government of India. 2013. Retrieved 26 January 2014.
- "Census Info 2011 Final population totals - Kayalpattinam". Office of The Registrar General and Census Commissioner, Ministry of Home Affairs, Government of India. 2013. Retrieved 26 January 2014.