[1] Extant (living) species are placed in a single order Charales,[2] commonly known as "stoneworts" and "brittleworts".

Fossil members of the class may be placed in separate orders, e.g. Sycidiales and Trochiliscales.

[3][4][5] In 2018, the first nuclear genome sequence from a species belonging to the Charophyceae was published: that of Chara braunii.

[7] Below is a consensus reconstruction of green algal relationships, mainly based on molecular data.

[8][9][10] Mesostigmatales Spirotaenia Chlorokybales Klebsormidiophyceae Charophyceae Coleochaetophyceae Zygnematophyceae Embryophytes (land plants)