The Kalmakkyrgan, also known as Bileuty (Kazakh: Белеуітті or Білеу; Russian: Билеуты), is a river in the Ulytau District, Karaganda Region, Kazakhstan.

In the early summer there are temporary camps of shepherds near the Kalmakkyrgan consisting of one or more yurts.

[8] The river has its sources near the southern slopes of Karamola mountain, southeastern Ulytau Range.

The river has its mouth in the southern end of the Shubarteniz lake, but its waters mostly get lost in the sands before reaching it.

[3] Its main tributaries are the Keregetassay, Amanzholsay, Duysembay, Sholaksay, Zhide and Bozingen from the right, as well as the Karsakpai, Talsay, Karatobesay, Ashylysay and Akkiiksay from the left.