Various examples are provided related to determination of contact angle of sessile drops. In one example, a method includes determining a volume of a sessile drop of fluid disposed on a test surface; determining a height of the sessile drop of fluid; and determining a contact angle of the sessile drop of fluid based upon the volume and the height of the sessile drop. In another example, a system includes a volume sensing, a height sensing, and computing that can determine a volume and height of a sessile drop using volume and height data from the sensing, and determine a contact angle of the sessile drop with the volume and the height. The contact angle and surface tension can be determined with at least three of volume, a height, a footprint radius, a radius of maximum horizontal extent, and/or an apex radius of curvature of the drop.