The incentral circle is the circumcircle of the incentral triangle. It has radius
 |
(1)
|
where 
is the area of the reference triangle and
 |
(2)
|
Its center function is a sixth-order polynomial that does not correspond to any Kimberling center.
Its circle function is
 |
(3)
|
corresponding to Kimberling center 
.
It passes through Kimberling centers 
for 
(Feuerbach point 
), 115 (center of the Kiepert
hyperbola), and 3024.
