Shaper Tool is a surfboard shaping definition developed on Grasshopper, a graphical algorithm editor integrated into Rhino 3D. It aims at simplifying 3D modelling of surfboards by algorithmically linking all the related parameters. With the tool it is possible to model an endless variety of surfboards through the variation of sliders. Due to its parametric nature, the user must simply alter the sliders to the desired value to automatically produce a working 3D model than can later be used for CNC production.