At the time of the 2006 National Census, the village's population was 1,163 in 277 households, when it was in Yunesi Rural District of the former Bajestan District of Gonabad County. The following census in 2011 counted 1,254 people in 345 households, by which time the district had been separated from the county in the establishment of Bajestan County. The rural district was transferred to the new Yunesi District. Sar Daq was transferred to Sar Daq Rural district created in the district. The 2016 census measured the population of the village as 1,254 people in 345 households.
^Sar Daq can be found at GEOnet Names Server, at this link, by opening the Advanced Search box, entering "-3082656" in the "Unique Feature Id" form, and clicking on "Search Database".
^ Davodi, Parviz (29 October 2019) [Approved 18 September 1386]. Approval letter regarding reforms of national divisions in Razavi Khorasan province, Gonabad County. rc.majlis.ir (Report) (in Persian). Ministry of the Interior, Political-Defense Commission of the Government Board. Proposal 93023/42/4/1; Notification 161409/T38028K. Archived from the original on 20 October 2020. Retrieved 8 November 2023 – via Islamic Parliament Research Center of the Islamic Republic of Iran.
