Every 3D print begins as a 3D model generated in a modeling program. Years ago, we had to spend lots of money and time to acquire and learn modeling software. Now, there are many easy-to-use modeling software options available, many of which are free. This list includes some of the best options and is sorted by price, with the free ones sorted alphabetically. The list also indicates whether the software uses solid modeling, a type of 3D modeling that always generates models that are “manifold” or “water tight.” A manifold model is one in which all walls of the model have some thickness, which is necessary for 3D printing. By contrast, software that uses polygon modeling can generate walls that have zero thickness; that’s fine for creating computer graphics for games and movies but not useful when 3D printing the models. Manifold models can be created with polygon modeling software, it just takes more steps and experience. All the software in this list can create 3D printable models, but every model that comes out of solid modeling software is 3D printable. Additionally, we’ve noted what skill-level of user each software is designed for: beginners, amateurs, advanced users, and professionals. In general, the easiest to use options are near the top and the most powerful options tend to be near the bottom, though there are some outliers found throughout. Most of these software can be tried for free and there are free tutorial videos available for all of them.