  Shape2SAS is a web application that allows researchers and students to build
intuition and understanding of small-angle scattering. It is available at
https://somo.chem.utk.edu/shape2sas. The user defines a model of arbitrary
shape by combining geometrical subunits, and Shape2SAS then calculates and
displays the scattering intensity, the pair distance distribution as well as a
visualization of the user-defined shape. Simulated data with realistic noise
are also generated. We demonstrate how Shape2SAS can calculate and display the
different scattering patterns for various geometrical shapes, such as spheres
and cylinders. We also demonstrate how the effect of structure factors can be
visualized. Finally, we show how multi-contrast particles can readily be
generated, and how the calculated scattering may be used to validate and
visualize analytical models generated in analysis software for fitting
small-angle scattering data.

Graphics;Biological Physics;Data Analysis, Statistics and Probability