* [http://www.mathalino.com/reviewer/derivation-of-formulas/derivation-of-formula-for-radius-of-incircle Derivation of formula for radius of incircle of a triangle]
* {{MathWorld |title=Incircle |urlname=Incircle}}
*[http://www.mathopenref.com/triangleincenter.html Triangle incenter] [http://www.mathopenref.com/triangleincircle.html Triangle incircle] [http://www.mathopenref.com/polygonincircle.html Incircle of a regular polygon] With interactive animations
*[http://www.mathopenref.com/constincircle.html Constructing a triangle's incenter / incircle with compass and straightedge] An interactive animated demonstration
* [http://www.cut-the-knot.org/Curriculum/Geometry/AdjacentIncircles.shtml Equal Incircles Theorem] at [[Cut-The-Knot]]
* [http://www.cut-the-knot.org/Curriculum/Geometry/FourIncircles.shtml Five Incircles Theorem] at [[Cut-The-Knot]]
* [http://www.cut-the-knot.org/Curriculum/Geometry/IncirclesInQuadri.shtml Pairs of Incircles in a Quadrilateral] at [[Cut-The-Knot]]
*[http://www.uff.br/trianglecenters/X0001.html An interactive Java applet for the incenter]
