| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Windows | — | Yes |
| macOS | — | Yes |
| Linux | Yes | Yes |
| Self-hosted | Yes | — |
| Plans published | 1 | 1 |
| Spec score · Physics Simulation Software | 8.6 (#12) | 8.4 (#15) |
| Audience | The project presents FDTDX for research, development, and commercial use in photonic nanostructure simulation and design. | The maker describes Xcos as suited to industrial and academic needs. |
| Authoring tools | Yes | Yes |
| Delivery mode | desktop | desktop |
| Free plan | Yes | Yes |
| Lesson library | No | No |
| Purpose | FDTDX is an open-source Python package for simulating and designing three-dimensional photonic nanostructures with the Finite-Difference Time-Domain method. | Xcos is a graphical editor for designing hybrid dynamical systems models in discrete and continuous time domains. |
| Support | The FAQ invites users to open GitHub discussions for unanswered questions and issues for suspected bugs, and says the maintainers regularly check discussions. | The Scilab history page says the company offers professional services and support for Scilab. |