| Price from | Free | Free |
| Free plan | Yes | Yes |
| Free trial | Yes | — |
| Open source | — | — |
| Web | Yes | Yes |
| Windows | Yes | Yes |
| macOS | Yes | Yes |
| Linux | Yes | Yes |
| iOS | Yes | Yes |
| Android | Yes | Yes |
| API | Yes | Yes |
| Self-hosted | Yes | Yes |
| Plans published | 4 | 1 |
| Spec score · Mail Server Software | 8.4 (#2) | 8.0 (#11) |
| Collaboration | Features include calendars, tasks, notes, contacts, shared folders, and sending email on another user's behalf. | Kolab provides shared email folders, calendars and task lists with granular access control, video conferencing and collaborative document editing. |
| Deployment | The product is downloadable for Linux and Windows and offers Docker images and Kubernetes deployment with AxiHelm. | Kolab is packaged as containers that can run on one host or be distributed across a larger environment. |
| Product | Axigen is an all-in-one email, calendaring, and collaboration platform for organizations from small businesses to large service providers. | Kolab is a free and open-source communication and collaboration solution that can be run on your own infrastructure. |
| Security | Listed protections include authentication and encryption, access and flow controls, SPF, DKIM, DMARC compliance, and two-step verification. | The feature page lists PGP, two-factor authentication, DKIM/DMARC and spam protection among its email security features. |
