OPNsense
| Developer | Deciso B.V. |
|---|---|
| OS family | FreeBSD (14.2-RELEASE) |
| Working state | Current |
| Source model | Open source |
| Initial release | 5 January 2015 |
| Latest release | 25.1.9 / 18 June 2025 |
| Repository | |
| Platforms | x86-64 |
| Kernel type | Monolithic kernel |
| Influenced by | M0n0wall. pfSense |
| License | Simplified BSD / FreeBSD License |
| Preceded by | m0n0wall |
| Official website | opnsense |
| Support status | |
| Community & Commercial | |
OPNsense is an open source, FreeBSD-based firewall and routing software developed by Deciso, a company in the Netherlands that makes hardware and sells support packages for OPNsense.
Launched in 2015, it is a fork of pfSense, which in turn was forked from m0n0wall built on FreeBSD. When m0n0wall closed down in February 2015 its creator, Manuel Kasper, referred its developer community to OPNsense.