OPNsense

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.

OPNsense
Developer	Deciso B.V.
OS family	FreeBSD (14.3-RELEASE)
Working state	Current
Source model	Open source
Initial release	5 January 2015; 10 years ago (2015-01-05)
Latest release	25.7.1[1]  / 31 July 2025; 0 days ago (31 July 2025)
Repository	github.com/opnsense/
Supported platforms	x86-64
Kernel type	Monolithic kernel
Influenced by	M0n0wall. pfSense
License	Simplified BSD / FreeBSD License[2]
Preceded by	m0n0wall
Official website	opnsense.org
Support status
Community & Commercial

Launched in 2015,^[2] it is a fork of pfSense, which in turn was forked from m0n0wall built on FreeBSD.^[3] When m0n0wall closed down in February 2015 its creator, Manuel Kasper, referred its developer community to OPNsense.^[4]

Features

OPNsense has a web-based interface and can be used on the x86-64 platform.^[5] Along with acting as a firewall, it has traffic shaping, load balancing, captive portal and virtual private network capabilities, and others can be added via plugins.^[6][7]

The software also offers next-generation firewall capabilities utilizing Zenarmor, a NGFW plugin developed by OPNsense partner^[8] Sunny Valley Networks.^[9]

Domain dispute

In November 2017, a World Intellectual Property Organization panel found that Netgate, the copyright holder of pfSense, used the domain opnsense.com in bad faith to discredit OPNsense, and obligated Netgate to transfer domain ownership to Deciso.^[10]

Releases

The OPNsense version naming system consists of year.month, since the first release took place in January 2015, it was named release 15.1. OPNsense typically uses a 6 month major release cycle with new releases in January and July of each year.^[11]

OPNsense Release History
Version	Code name	General availability	Latest minor version	Latest release date	Major changes
15.1[12]	Ascending Albatross	2015-01-05	15.1.12	2015-06-17	Initial release
15.7[13]	Brave Badger	2015-07-02	15.7.25[14]	2016-01-18	Base proxy and IDS support pfSense config importer FreeBSD 10.1
16.1[15]	Crafty Coyote	2016-01-28	16.1.18[16]	2016-06-30	Firmware mirror location and crypto selection IPS FreeBSD 10.2
16.7[17]	Dancing Dolphin	2016-07-28	16.7.14[18]	2017-01-25	RFC 4638 support (MTU > 1492 in PPPoE) HTTPS proxy support Active Queue Management (AQM): Controlled delay (CoDel) and FlowQueue-CoDel Two factor authentication using RFC 6238 HardenedBSD's ASLR implementation UEFI/GPT boot FreeBSD 10.3
17.1[19]	Eclectic Eagle	2017-01-31	17.1.11	2017-07-25	PHP 7.0 Lets Encrypt plugin Pluggable firewall rules Load Balancer, UPnP, SNMP, IGMP, WOL as plugins FreeBSD 11
17.7[20]	Free Fox	2017-07-31	17.7.12[21]	2018-01-18	HardenedBSD SafeStack for base applications and selected ports HardenedBSD procfs hardening Interface code speedup
18.1[22]	Groovy Gecko	2018-01-29	18.1.13[23]	2018-07-24	Debug kernel support PHP 7.1 pluggable NAT rules FreeBSD 11.1
18.7[24]	Happy Hippo	2018-07-31	18.7.10[25]	2019-01-07	Meltdown and Spectre V2 mitigations Intel NIC driver updates IDS/IPS application detection rules FreeBSD 11.2
19.1[26]	Inspiring Iguana	2019-01-31	19.1.10[27]	2019-07-03	Firewall NAT rule logging support WPAD / PAC and parent proxy support in the web proxy 2FA via LDAP-TOTP combination Dnsmasq DNSSEC support HardenedBSD 11.2
19.7[28]	Jazzy Jaguar	2019-07-17	19.7.10[29]	2020-01-09	PHP 7.2 LibreSSL 2.9 WireGuard plugin Firewall rule statistics
20.1[30]	Keen Kingfisher	2020-01-30	20.1.9[31]	2020-07-23	Google backup API 2.4.0 LibreSSL 3.0 Support elliptic curve TLS certificate creation VXLAN support Support for additional loopback interfaces
20.7[32]	Legendary Lion	2020-07-30	20.7.8[33]	2021-01-19	Basic firewall API support (via additional plugin) Suricata 5 Unbound + DHCPDv4: Properly support expired leases PHP expand code styling to PSR-12 HardenedBSD 12.1
21.1[34]	Marvelous Meerkat	2021-01-28	21.1.9[35]	2021-07-27	Fix stability and reliability issues with regard to vmx(4), vtnet(4), ixl(4), ix(4) and em(4) Ethernet drivers LibreSSL 3.2 New and improved live traffic report IDPS: New policy definition using metadata tags (e.g. drop all critical events aimed at the perimeter)
21.7[36]	Noble Nightingale	2021-07-28	21.7.8[37]	2022-01-27	Migrate bsdinstaller to bsdinstall AXGBE 10 Gbps network card driver inclusion PHP 7.4 NTPD client mode Firmware Update Revamp Firewall states diagnostic API/GUI
22.1[38]	Observant Owl	2022-01-27	22.1.10[39]	2022-07-07	Authentication / LDAP automatic user creation on login Improve alias hostname resolve performance Improved firewall statistics Support overload table on max new connections FreeBSD 13
22.7[40]	Powerful Panther	2022-07-28	22.7.11[41]	2023-01-18	Intel QuickAssist (QAT) support Add stacked VLAN support (IEEE 802.1ad / QinQ) Advanced DDoS protection using syncookies PHP 8.0 FreeBSD 13.1
23.1[42]	Quintessential Quail	2023-01-13	23.1.11[43]	2023-06-28	Firewall alias BGP ASN type support DNS insights dashboard PHP 8.1 WireGuard kernel module LibreSSL discontinued
23.7[44]	Restless Roadrunner	2023-07-31	23.7.12[45]	2024-01-16	Support for Importing Encrypted Configuration Files During OPNsense Installation RADIUS Authentication - Add MSCHAPv2 support Intrusion Detection: Suricata Netmap API version 14 enabled PHP 8.2 FreeBSD 13.2
24.1[46]	Savvy Shark	2024-01-30	24.1.10_8[47]	2024-07-25	Suricata 7 OpenSSL 3 ports migration NPTv6 migrate to MVC VXLAN: add support for non standard port numbers os-firewall plugin inclusion to ease API usage Improve WireGuard kernel plugin and implement it in core Add Kea DHCP server option as an alternative to ISC DHCP which will eventually be deprecated
24.7[48]	Thriving Tiger	2024-07-25	24.7.12[49]	2025-01-15	Python 3.11 FreeBSD 14.1 PHP 8.3 Modern dashboard UI improvements Several MVC migrations (GIF, GRE, NAT, dhcrelay) WireGuard VPN performance improvements WireGuard client QR code generation ISC dhcrelay deprecated Captive portal fixes and improvements
25.1[50]	Ultimate Unicorn	2025-01-29	25.1.12[51]	2025-07-22	FreeBSD 14.2 PHP 8.3 ZFS snapshot support Updated UI with new dark theme Several MVC/API migrations
25.7	Visionary Viper	2025-07-23	25.7.1[52]	2025-07-31	FreeBSD 14.3 Updated firewall automation GUI Frontend overhaul Alias performance enhancement Dnsmasq DHCP support (default DHCP server switched from ISC to Dnsmasq) Kea DHCPv6 support SFTP backup plugin
Legend:   No longer supported versions   Latest supported release

See also

• Free and open-source software portal

• List of router and firewall distributions