Sad ol Din (Persian: سعدالدين)[a] is a village in, and the capital of, Kavir Rural District, Sheshtaraz District, Khalilabad County, Razavi Khorasan province, Iran.

[4] At the time of the 2006 National Census, the village's population was 1,965 in 533 households.

[6] The 2016 census measured the population of the village as 1,931 people in 646 households.

It was the most populous village in its rural district.

This Khalilabad County location article is a stub.