What is OPNsense used for?

OPNsense is an open-source firewall and routing platform; this repository holds its web GUI, API and system backend, licensed under BSD-2-Clause. It is a good fit for home or office network firewall, perimeter security and VPN gateway, and guest access with a captive portal.

Is OPNsense open source?

Yes. OPNsense is open source under the BSD-2-Clause licence. Its source code is on GitHub at opnsense/core and is written mainly in PHP.

Yes. OPNsense is open source, so the software itself is free to use.

Can I self-host OPNsense?

Yes. OPNsense can be self-hosted on your own server or infrastructure; there is no official hosted version.

What is OPNsense an alternative to?

OPNsense is an open-source alternative to Fortinet, Palo Alto Networks, Check Point and Sophos. Other open-source alternatives to Fortinet include pfSense, Suricata and ModSecurity.

Is OPNsense actively maintained?

Yes. The most recent commit to OPNsense was on 2 October 2026. The project has 4.7k stars on GitHub.

OPNsense: open-source alternative to Fortinet

About OPNsense

OPNsense is an open-source firewall project, and this repository contains its web GUI, API and systems backend. Its topics point to a broad feature set that includes a firewall, intrusion prevention, proxy, VPN, traffic shaping, a captive portal and routing, built on a BSD base.

The project invites developers to contribute and has designed its build process so that anyone can build and write code. Build tools are freely available in a separate tools repository, an architecture overview is on docs.opnsense.org, and the repository offers Makefile targets such as make package for assembling a package from the current state of the code. The team aims to evolve toward a new codebase gradually rather than in one big switch.

OPNsense is written mostly in PHP and is committed to staying available under the 2-clause BSD license, with every contribution required to carry the same terms. Contributions can be as simple as testing functionality, filing bug reports or sending pull requests.

Key features

Web GUI for firewall management
API and system backend
Intrusion prevention and proxy
VPN and traffic shaping
Captive portal and routing
BSD-based platform

Good fit for

→Home or office network firewall
→Perimeter security and VPN gateway
→Guest access with a captive portal

Built with: PHP
Tags: firewall; router; vpn; ips; bsd; captive-portal; traffic-shaping; security; networking

OPNsense: questions and answers

What is OPNsense used for?: OPNsense is an open-source firewall and routing platform; this repository holds its web GUI, API and system backend, licensed under BSD-2-Clause. It is a good fit for home or office network firewall, perimeter security and VPN gateway, and guest access with a captive portal.
Is OPNsense open source?: Yes. OPNsense is open source under the BSD-2-Clause licence. Its source code is on GitHub at opnsense/core and is written mainly in PHP.
Is OPNsense free?: Yes. OPNsense is open source, so the software itself is free to use.
Can I self-host OPNsense?: Yes. OPNsense can be self-hosted on your own server or infrastructure; there is no official hosted version.
What is OPNsense an alternative to?: OPNsense is an open-source alternative to Fortinet, Palo Alto Networks, Check Point and Sophos. Other open-source alternatives to Fortinet include pfSense, Suricata and ModSecurity.
Is OPNsense actively maintained?: Yes. The most recent commit to OPNsense was on 2 October 2026. The project has 4.7k stars on GitHub.