| Price from | €11.61/mo | Free |
| Free plan | Yes | Yes |
| Free trial | — | — |
| Open source | — | — |
| Web | Yes | — |
| macOS | — | Yes |
| Linux | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 7 | 1 |
| Spec score · Mail Server Software | 8.0 (#12) | 7.4 (#28) |
| Purpose | Modoboa is an open-source platform for installing and managing a self-hosted email server. | OpenSMTPD implements server-side SMTP and lets machines exchange email with systems that speak SMTP. |
| Support | The project offers paid installation or upgrade assistance, help with specific issues, and annual maintenance services. | The project is volunteer-developed and is not backed by a commercial entity. |