Kostanay or Qostanai (Kazakh: Қостанай, pronounced [qostɑˈnɑj] (listenⓘ), Russian: Костанай, IPA: [kəstɐˈnaj]) is a city located on the Tobol River in northern Kazakhstan.

[2] Kostanay was founded by Russian settlers in 1879 and named Nikolaevsk, in honor of Tsar Nicholas II.

The nearest city with at least a million inhabitants is Chelyabinsk in Russia, located 260 km north-west of Kostanay.

Average wind speed is 3.2 metres per second (12 km/h; 7.2 mph; 6.2 kn), mainly from the south in winter and from the north in summer.

[3] Kostanay is connected by road with the following cities in Russia: Chelyabinsk, Magnitogorsk, Troitsk, Yekaterinburg, Kurgan and Tyumen.

Kostanay International Airport handles common and charter flights to many cities in Kazakhstan, former Soviet republics, Germany (Frankfurt and Hanover), the United Arab Emirates, Turkey, and other countries.

The city has an ice rink for winter sports, and in 2016, a team participated in the national bandy championship in Khromtau for junior players born in 1999–2000.