The visualization tool MARDIGRAS (Mass-Radius DIaGRAm with Sliders) enables simple and intuitive manipulation of mass-radius relationships (also known as iso-composition curves) using interactive sliders. It infers composition based on mass and radius (and other parameters). As a result, it requires use of actual measurements of mass and radius; values that are upper/lower limits, derived from empirical mass-radius relations, or are somewhat controversial should not be used. MARDIGRAS screen captures can be used for general scientific communication but are not of suitable quality for article publication.

GASTLI (GAS gianT modeL for Interiors) calculates the interior structure models for gas giants exoplanets. The code computes mass-radius curves, thermal evolution curves, and interior composition retrievals to fit a interior structure model to your mass, radius, age, and if available, atmospheric metallicity data. GASTLI can also plot the results, including internal and atmospheric profiles, a pressure-temperature diagram, mass-radius relations, and thermal evolution curves.