4 Best Open source custom router firmware

The router we have in our home are from different manufacturers such as Netgear, TPlink, Linksys, Asus, Digisol, Dlink etc. All of them has different stock firmware and security features. Many times to save money, we go for some cheap option and here the problem starts because their functions and security features are limited, that makes them unreliable. One reason for saying this is the availability of updates and patches for router firmware. Most of the time either the manufacturers not supplying the updates, even if they are, the user not aware of them. Among them, sometimes well-known router companies also do not bother to patch the security loopholes, especially for few years’ old routers. In such situations, hackers could perform the malicious activities to breach the weak security of your network.

Thus, you have to take network security command in your hand. If you have a bit knowledge of technology and Linux you can use the custom open source router firmware.

Best Open source custom router firmware

What is Open source router firmware?

The Open source router firmware also is known as custom router firmware or aftermarket firmware or alternative router firmware. These type firmware can prove the best alternative OS to router’s stock firmware.

The custom router firmware not only provides you the best available security features but also give you a chance to modify them as it based on Linux; in order to make your router more advance or add some additional features to suit the office or home requirements.

So, here, we are going to show the best available open source router firmware those keep updating and adds security to protect all devices connected to a router to access the internet.

Benefits of using Open source router firmware

  • Removes bugs available in stock firmware.
  • Removes any government restrictions or backdoors used to spy
  • You can edit the firmware code.
  • Improved user interface
  • Allow adding different functionality.
  • VPN integration
  • Caching
  • Telnet/SSH support
  • Wifi hotspot integration
  • Network stability
  • Advance wireless modes
  • Vlan
  • Full control over the network routing
  • And more…

List of best free & open source firmware projects available for different wireless and wired routers. You can run these custom router software on a branded routers like Linksys, Netgear etc..

Top & Best Open source custom router firmware

OpenWrt Project

Openwrt router firmware

It is a kind of Linux operating system which is one of the oldest router firmware in the market, since 2004.  It is meant for embedded devices, obviously routers. It is not a single static firmware instead of that it provides a access to the filesystem which writable with package management. Generally, the Customer-premises equipment (CPE) routers are supported by the OpenWRT router but besides that, it can be run on residential gateways, smartphones, and personal computers (x86) to use them as routers.

It is free of cost custom router firmware and the user can configure and customize to suit any application. The main components of this custom router firewall are Linux, util-linux, musl, and BusyBox.

Initially, the OpenWrt worked on the command line only and later for users convenience the Graphical user interface was developed. However, to work with the GUI your router should have minimum 8MB flash storage and for command line 4MB. This shows that the graphical user interface is optional; if you are comfortable with the command line you use that only. Also, as you can see it is a very old but still live open source router project and that’s why there are different UIs available created by different community users. It also offers 3500 optional software packages those can be installed using the opkg package management system. It required 32MB RAM for stable operation while 64MB would be better.

Supported OpenWRT router list: Before downloading and flashing it on your router please the see the list of router those supported by the OpenWRT, here is the link.

OpenWrt features:

  • High level of customization
  • IPv4 support
  • IPv6  support includes native IPv6 configuration (SLAAC, stateless DHCPv6, stateful DHCPv6, DHCPv6-PD), IPv6 transitioning technologies (6rd, 6to4, 6in4, ds-lite, lw4o6, map-e), Downstream IPv6 configuration (Router Advertisement, DHCPv6 (stateless and stateful) and DHCPv6-PD).
  • Routing through iproute2, Quagga, BIRD, Babel etc.
  •  B.A.T.M.A.N., OLSR and IEEE 802.11s-capabilities of routing protocols
  • Wireless functionality such as a wireless repeater, a wireless access point, a wireless bridge and more
  • Wireless security
  • Stateful firewall, NAT, and port forwarding
  • Dynamically-configured port forwarding protocols UPnP and NAT-PMP through upnpd, etc.
  • Load balancing
  • IP tunneling (GRE, OpenVPN, pseudowire, etc.)
  • Domain Name System (DNS) and DHCP through Dnsmasq, MaraDNS, etc.
  • Wireless distribution system (WDS) including WPA-PSK, WPA2-PSK, WPA-PSK/WPA2-PSK Mixed-Mode encryption modes
  • OpenWrt supports any hardware that has Linux support
  • Software packages support to use hardware
  • And more…


DD-WRT open source custom router project

It is another best OpenSource router firmware based on Linux.  It was released in 2005 and borrow the WRT in its name form popular Linksys WRT54G router series because it was specifically designed for them at that time.  It comes in different sizes and flavors such as Micro (2 MB),  Mini (4 MB),  Nokaid (4 MB),  Standard (4 MB), VOIP (4 MB), VPN (4 MB), and Mega (8 MB). The Mega version which requires 8MB of space supports all features of the DD-WRT such as:

  • ChilliSpot
  • Web management over HTTPS
  • IPv6
  • JFFS2
  • XLink Kai daemon
  • MMC & SD card support
  • NoCat
  • OpenVPN
  • PPTP client
  • radvd
  • RFlow (traffic information)
  • Samba/CIFS client
  • Milkfish SIP router
  • SNMP Yes
  • Secure Shell daemon
  • Wiviz

In the default state, the DD-WRT lack some features as compared to the OpenWRT; to solve this it supports the third party builds to enhance the functionality. Also, its tabbed design user interface is very easy to operate and be handled by any non-technical user. The user can even change the default color scheme of the router interface which is blue and black. Things did not stop here beside tonnes of useful feature it also allow overclocking of the router.

Before downloading the DD-WRT see the list of supported routers, here is the link. (Just enter three initial words of your router name to identify its support.)

Beside the above-mentioned features of the DD-WRT it also supports:

  • Access control
  • Bandwidth monitoring
  • Quality of service
  • WPA/WPA2 (personal and enterprise)
  • iptables firewall
  • Universal Plug and Play
  • Wake-on-LAN, Dynamic DNS
  • AnchorFree VPN
  • wireless access point configuration
  • multiple SSIDs
  • overclocking
  • DD-WRT’s support for OpenVPN, WireGuard
  • And more…

Tomato Router Firmware

Tomato router frimware open source

Tomato is based on the HyperWRT router project but unfortunately, that stopped getting updates in 2006, however, the Tomato keeps the momentum and still getting an update.  It is not completely opensource but a free custom router firmware with beautiful aesthetically designed themes. You can see a lot of use of Ajax as well as an SVG-based graphical bandwidth monitor. It supports a wide range of older Linksys WRT54G series, Buffalo AirStation, Asus routers and Netgear WNR3500L. The Linksys WRT54G/GS v5 or newer WRT54G/GS routers will not work with the Tomator router frimware.

Routers supported by Tomato:


  • WRT54GL v1.x
  • WRT54G v1-v4
  • WRT54GS v1-v4
  • WRTSL54GS (no USB support)


WHR-G54S, WHR-HP-G54, WZR-G54, WBR2-G54, WBR-G54, WZR-HP-G54, WZR-RS-G54, WZR-RS-G54HP, WVR-G54-NF, WHR2-A54-G54, WHR3-AG54


  • WL520GU (no USB support)
  • WL500G Premium (no USB support)
  • WL500GE


  • WX6615GT
  • Fuji RT390W
  • Microsoft MN-700

Because of the nice community support, this router project is still flourishing. Just like the DD-WRt, the Tomato also has some community modes to add extra functionality. The latest release of the Tomato mode called FreshTomato
Mod in 2018.3 beta version which was public on July 22, 2018, has a wide range of feature support such as VPN, PPTP, USB support, SD card, VLAN, IPv6, 5GHz band, overclocking, multilan and more…  However, still is behind the DD-WRT and if someone looking for simple GUI interface to easily operate the router then it would be the choice but not for users, those need advanced features.

Tomato  key Features:

  • Ajax based GUI
  • SVG based graphs
  • CLI access (BusyBox) via Telnet or SSH (using Dropbear)
  • DHCP server
  • Client bandwidth control via QoS classes
  • Bandwidth statistics and graphing
  • DNS forwarder (using Dnsmasq)
  • Netfilter/iptables with customizable settings, IPP2P and l7-filter
  • Wireless modes:
  • Access point (AP): Wireless client station (STA), Wireless Ethernet (WET) bridge, Wireless distribution system (WDS also known as wireless bridging), Simultaneous AP and WDS (also known as wireless repeating)
  • Syslog viewable through the GUI
  • Wake-on-LAN
  • Advanced QoS
  • SES button control, JFFS2, SMB client and more…

Before download, the Tomato router check your router compatibility: Link



Gargoyle open source custom router frimware

Gargoyle is based on OpenWrt which is another free router Linux distribution. It mainly meant for Broadcom or Atheros based chipset routers, for example, older Linksys WRT54G series, Asus Routers and Netgear routers. It is interface developed keep in mind the ease of usage. Both command line and the graphical user interface is available on the Gargoyle.

Gargoyle key features

  • Tor server and Tor client.
  • Adblocker.
  • Network file storage sharing, SMB, CIFS.
  • VPN server and VPN client.
  • Wifi scheduled on/off.
  • Bandwidth monitoring
  • Quotas, limits and bandwidth throttling
  • Quality of service (QoS) with active congestion control
  • Website blocking by hostname or IP address

Check out the Supported router architecture by Gargoyle: Link

Few other available open source router projects or tools






Top Few free and open source router + firewall distributions for PC or servers…

Below give router and firewall distributions are not for the router’s hardware, instead of that one can use them in dedicated computer or servers hardware.



Endian Firewall


SME Server