Best Free Firewall Protection

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Firewalls help monitor your system's communications between your network and the Internet, to help detect, alert, and prevent intrusions and attacks. They are particularly useful for controlling the activities of Internet facing applications, ie. applications that access the internet.

Firewall products can be one of more cumbersome software products to use and have a reputation of causing user angst - to find a suitable product that meets individual users' needs may involve a process of trial and error. A good firewall should be able to protect the user at a near-perfect level, while not being too intrusive or complicated to handle. In this article, we give you a selection of some of the best free firewall software, in our opinion, that is available. Our reviews and recommendations are made taking into consideration both editors' and site visitors' experience, opinions, and comments. As always, if you have more to share on your experiences with the software products mentioned and/or freeware firewall products that you like, we would like to hear from you. Please refer to the comments section at the bottom of this page.

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Review Index


Basic Firewalls

The built-in Windows firewall is a common and popular choice since it passes all inbound tests (both stealth and open port), doesn't have many popup alerts, and doesn't cause system performance issues. It also does not require a separate software installation, since it comes built-in with modern versions of Windows. The built-in Windows firewall has improved drastically from earlier versions of Windows; the latest iteration, Windows 10, now contains a very capable and reliable built-in firewall solution, which is named Windows Defender Firewall.

You can also replace the Windows firewall with a basic third-party firewall which can provide greater control of outbound protection and additional features. Most simple two-way firewalls ask you to allow or deny Internet access for unknown programs. Many also automatically allow trustworthy apps and remember your decisions to become silent over time. However, these software require additional configuration of settings, especially at the outset. With the improved functionality of the built-in firewall in Windows 10, such third party firewall solutions are decreasing in popularity.

Windows Defender Firewall  

A firewall built into Windows with no separate installation required.

Our Rating: 
License: Commercial
Built in to Windows, no separate installation needed, simple and easy to use, effective, passes all tests, no nagging or annoying pop ups, runs seamlessly and quietly in the background, significant improvements since initial version in XP. Current iteration in Windows 10 is suitable for most daily users,
Primarily incoming connecting protection only. Advanced user interface is not user friendly - this interface may not be suitable for beginner users. Would be beneficial paired with a third party tool such as Windows 10 Firewall Control. May not provide adequate protection for "high risk" users.
Read full review...


A lightweight firewall solution that works with the built-in Windows Firewall.

Our Rating: 
License: Free
Lightweight basic firewall; simple yet effective. Non-intrusive program with no pop-ups. Ability to recognize associated processes when white-listing programs. This program could be a good choice for those not familiar with computers, as it does not require advanced knowledge to use.
No user dialog; everything is accessed from the pop-up menu. Not necessarily a bad thing, but may be different compared to what most are used to. Cannot select where to install the program. Requires .NET framework.
Read full review...

Windows 10 Firewall Control  

A good choice to supplement the Windows built-in Firewall and compatible with Windows XP and higher.

Our Rating: 
License: Free (Limited features)
Simple and effective; uses Window's built-in firewall platform so no third party kernel drivers are needed. Very small footprint. Three modes to choose from (Normal, EnableAll or DisableAll). Great for complementing Windows' built-in firewall.
May be a bit annoying to use at first since the user must configure the initial rules for all their applications; no training mode. The dialog box that pops up to allow/disallow a particular program has a lot of information, some of which may not be too user friendly to beginner computer users. Online manual could be more comprehensive.
Read full review...

ZoneAlarm Free Firewall  

A well-established inbound and outbound OS firewall solution suited for users of every level of experience.

Our Rating: 
License: Free (Limited features)
Solid inbound firewall, stealth mode, user friendly, customizable settings, anti-phishing protection, and hosts file lock.
Inadequate HIPS or program monitoring protection. No High setting for program access in Free version. In spite of available automatic update option, updates almost always must be performed manually. Help file designed for commercial version.
Read full review...

Firewalls with HIPS Protection

The following personal firewalls provide an advanced level of network and HIPS protection. Each firewall comes with default settings and, depending on the users' needs, may or may not require much adjustments.

It should be noted that firewall products in this section require more time to learn and configure, and are more complex to use than basic firewalls. There is also a higher risk of conflicts and problems arising on your system. Since firewalls are often praised for their security effectiveness at their max settings, users will likely have lower protection than mentioned by independent testing sources, such as Matousec, for practical day to day use. All of the product vendors seek to provide user friendly features, sometimes incorporating reduced levels of protection in their default settings by decreasing some HIPS monitoring. In other words, these firewalls may be more suitable for more advanced users, as well as those that are more "high risk". We would only recommend these firewalls for these users; for average daily users, basic firewalls are likely sufficient.

Comodo Firewall  

A good choice for lightly-skilled and advanced users seeking a full featured security suite.

Our Rating: 
License: Free
Its Defense+ HIPS performance exceeds commercial products and leads the class, it includes a "memory firewall" feature, and it allows you to quickly switch between Defense+ security modes and configurations. Includes automatic updates. Installation can automatically configure your PC to use the Comodo SecureDNS (but you can do this without installing CIS).
No built-in help. Despite not installing the AV component, the AV files are still placed in the Comodo program folder. Possible problems when uninstalling program; remnants of the program are sometimes left on the computer.
Read full review...


Both types of firewalls (basic and HIPS/proactive) both have their benefits and drawbacks. While HIPS software do offer greater protection and control of your machine, it naturally requires more user interaction and resources, making such software more complex. There are more settings to configure than basic firewalls.

On the contrary, basic firewalls are generally simpler to use and may be easier for the user to adjust and learn how to use it. Comparatively, they do not offer as much protection as HIPS software; for example, they cannot detect suspiciously acting software behaviour, as it primarily filters incoming and outgoing internet traffic.

If you are an advanced computer user and/or are a "high risk" user, then the increased complexity of a HIPS firewall may be the best option for you, as it offers you the maximum protection available (in this regard). However, for most average users who use their computer for regular day to day use, a basic firewall, especially the built in Windows Defender Firewall, is probably more than adequate. For these latter parties, a HIPS firewall may simply be going overboard as the increased features, complexity, and configurations are unnecessary.


Additional Tips / Precautions

  • Before installing new resident security products, including antivirus and firewall programs, consider making a full drive image. By creating a full drive image you are able to restore your entire computer back to a previous state in the event your system becomes completely unresponsive. Drive imaging allows you to recover from unintentional conflicts as well as severe malware infections. Everyone's system is unique and may have old, latent drivers that may be incompatible with whatever you are installing, causing problems with your system. Newer versions of Windows have a built in "Complete PC Backup and Restore" feature, or you can use a free drive imaging program
  • To cleanly uninstall your (third-party) firewall before installing a new one, you may consider using ZSoft Uninstaller to analyze before and after the installation. If you haven't used it on your current firewall, try Revo Uninstaller (or other vendor or Windows uninstaller), check for leftover services and drivers with Autoruns, and restart your computer.


Other/Unsupported Firewalls

The following firewalls are now unsupported by their vendors. This means they have been discontinued and/or are no longer offered by the software publisher. While they may still be available for download, they may contain undocumented bugs or stability/security issues that will not be addressed. These reviews are archived for information purposes only. Unless you run an older Windows system with no other current firewall programs available and are unable to upgrade, we recommend using an active, supported program from the list above. 

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Related to Firewalls

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This software category is maintained by volunteer editor Tim. Registered site visitors can contact Tim by clicking here.

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Average: 4.3 (546 votes)


I would not recommend WinPatrol for their firewall or any of their products.
I was one of the first people to have a lifetime license for WinPatrol and for many years extolled its virtues.

Unfortunately, the original developer became ill and sold the product rights.
The new owner seemed to be doing decent work for a while, but due to a series of events he stopped development of any of the WinPatrol products in 2017.

Unlikely that security programs that have not been updated in close to three years will provide any real protection.

There is also no support for any of these products.

Seems wrong to me that he is still selling a product that is neither supported or developed.

winpatrol firewall. is paid, but has free version with limitations. after trial it used to go to free version.

and what about glasswire firewall? i think xvirus might even have a free after trial with limitations, (but with them, i am not sure).

This section is really disappointing. We need to know about firewalls. Comodo is not the answer for many of us, not trustworthy any more, slows things down. Zonealarm is US based and probably hooked up to NSA. Is there nothing free and decent out there which does not require a degree in Computer Security to set up???

Back in 2014 AV Comparatives was commissioned to conduct an independent test of firewalls and the Windows firewall outperformed everything. In fact most of the third party apps actually reduced the level of security once installed. This is one reason why the number of third party firewalls has declined. They are no longer necessary. Those that do exist do so mostly as a platform to sell other products rather than perform any useful function. MC – Site Manager. The .pdf report of this test is no longer available on their site but this is a copy of the conclusion from it.

Of twelve Internet security suites tested, only five provided full protection in public networks.
Another two allowed Remote Desktop connections to be made using IP addresses; whilst this does not
affect users with Home editions of Windows, it could represent a significant security risk to business
users with Professional, Business or Enterprise versions of Windows. One further suite can provide full
protection if it is manually configured (and the PC restarted after connecting to the network), but
this can only be done by advanced users with an understanding of TCP/IP networking. For the average
user, the suite’s firewall effectively allows all forms of access in public networks. The remaining four
allow both file sharing and Remote Desktop access in public networks, even in cases where the LAN
has been registered as public in the suite’s own settings.
Six out of the seven manufacturers whose suites fail to provide complete protection make a
standalone antivirus program without firewall, which can usually be purchased more cheaply than the
corresponding full Internet security suite. However, most manufacturers claim in their advertising
that the more expensive suite will protect the user’s computer better than the simple antivirus
program. This test indicates that half of the security vendors are actually charging more money for a
product that may provide significantly less security in some situations, and that users would do better
to buy the simple antivirus program and rely on Windows Firewall to prevent unauthorised intrusion.
We note that a number of major vendors are nowadays not including their own firewalls in their
security suites, but relying on Windows Firewall instead, as this provides suitable protection and is
easy to configure.
In the case of the four standalone firewalls, all allowed both file sharing and Remote Desktop access
in public networks, even in cases where the network has been set to Public/Untrusted in the program
itself. We would suggest that enthusiasts who use such programs should consider whether the
advanced features provided in these programs make up for the lack of basic protection in public

Thanks MC. I do agree with you / the article that WDF is enough in most cases.

I have a laptop that I use a lot for travel and used (commercial reference removed as per site rules) I use a VPN when travelling, but it does not kick in immediately after connecting, and very often you have to register with a hotel or other wifi first to be able to get the connection established, then you can enable VPN. It's during that period oftime that I feel really exposed.

I've used Comodo FW before but had too many issues with it. Zonealarm doesn't do program control and probably misses other functions too. Privatefirewall was ideal for me back in Win 7 days. Hence my frustration at not finding another solution. I've tried the various outbound firewall control softwares on this site but they are too manual for me.

It`s a pity the .pdf test report is no longer available from AV Comparatives. The commercial program you enthuse about so much failed in 5 separate areas and actually reduces your security compared to Windows firewall from the moment it is activated. The problem is folks believe the hype on the vendor`s website and end up buying the product. The same applies to so called registry cleaners that provide no useful function other than to generate profits for the vendors and cause multiple installations of Windows to need reinstalling. :)

ZoneAlarm does have program control.

This is actually a good example of why it is necessary to have a proper understanding of security apps before deciding to dump the perfectly good set of default applications provided with Windows. If you don't even know what a particular third party program offers how can you possibly configure it correctly and decide it is better than the Windows default?

Overall from the set of circumstances you describe you would be far better off using Linux as I do for all my business and personal needs. MC - Site Manager

Your analogy is akin to "If you can't work through the electronics interface in your 2015 Impreza, you would be better off trading in for a 2019 Volvo." That is, trade the limited sequence of options to set and learn (and then decide whether to keep) a basic FREE Firewall, versus making an entire continental leap to a potentially advantageous OS, but with well-known HUGE learning curves, that in the end might or might not solve networking or security issues, but which will definitely result in weeks if not seasons' worth of effective computer down time while you laboriously and tediously try to figure out the damn Linux galaxy.
I have found it far easier to just use Free Macrium Reflect image software to back up my entire Drive, at least the OS related partitions, then try stuff out without worries. Windows system restore is notoriously inconsistent, regarding what does and does not get properly restored. FWIW, I'm about to dump the Online Armor Firewall I've used to protect an old XP machine, because it unchecks the Trusted box of my Broadcom ethernet controller with every reboot, and constantly pops up alerts about program behaviors that are impossible to distinguish from valid, necessary ones. SpyShelter is another overbearing, overprotective layer that constantly invokes paranoia, without meaningful differentiation regarding actual threat levels from myriad processes. I last paid for a firewall and backup software when tape drives were the benchmark, and both failed when needed. VPN or hardened firewalls may be necessary when using a PC on public WiFi, but for home use within a router-based personal network, Windows Firewall and Security Essentials have worked fine for Win 7 going on ten years.

Although I am clued up on IT pretty well, I've always struggled somewhat with networking and firewall detailed comprehension, or perhaps it's more about taking the necessary time to understand.

I have to run a business and at the end of the day I have to choose all of my various suppliers, free or commercial, that includes the software that runs on my computers. I've tried to go 100% with Linux several times, but driver and other issues stopped me from progressing. I also work in an MS Office workflow and LibreOffice is not good enough yet for me unfortunately. Also WINE does not work with my version of Office.

Anyway, what I'm getting to is that I review several review sites and the security software that I choose is via a calculation I do based on the freely available test result of 4 review sites: AV-Comparatives, AV-Test, MRG Effitas and SE Labs. Windows Defender has improved tremendously over the past year or two, but my commercial choice is one that does slightly better across all these test sites. I delegate my knowledge to them, teams of very experienced professionals who are hopefully protecting my machines, including at the network / firewall level, since I don't have all the time and experience that they do.

I'm not knocking your good point MC, just making my point that yes, WD and WDF is great, but for especially for a roving business laptop, I choose a commercial solution which gets consistently high marks on independent test sites and has what I understand to be a smarter firewall than WDF. I'm sure those tests that you referred to were spot-on, but products move on I'd be interested to see a similar test done today. For home or small office based computing WD, WDF + uBlock Origin and an occasional scan with the free Emsisoft and / or Malwarebytes scanners are enough for 99% of users in my view.

By the way, I'd forgotten in my previous post that another favourite firewall od mine was the PC Tools one and which I used at one point in conjunction with Threatfire, a great combo! Sadly swallowed up by bigger fish and no longer available, although I'm sure their technology lives on within new products.

Just thought I'd inform everyone that Privacyware site no longer exists. Bummer... This firewall is still available at Softpedia but is version NOT . If you install this firewall you will find out that the zero day protection and alot of other features no longer work because they are dependent on Privacywares server which no longer exists.

PrivateFirewall still outperforms most of the other Free options out there. Even without "Zero Day" features.
As for ver It is still freely available at a number of sites: Would recommend the TomsGuide site.,0301-33843.html

While I really like the firewall Comodo offers, I cannot use & will not recommend anyone else use, as you cannot fully disable the. anti-virus aspects of their software, even if you explicitly try to, or attempt to only install the firewall. i told it during installationthat I only wanted the firewall, but it gave me everything anyway, and while I had been running it before, even though I disabled the anti virus, it decided it would constantly block my attempts to run things and NEVER notify me about it, so I thought I was having computer problems. It took me forever to figure out Comodo was the damn culprit! Now it has earned itself a spot in my most loathed software, especially because of their greedy underhanded tactics to install crap you explicitly say you don't want, and then trying to ram their other products down your throat.

Hi, folks:

Guessed you might like to know about SimpleWall (1.6), an apparently promissing free firewall, with language support, available at .

Kind regards from Rio, Niterói, Brazil. ;)

Comodo all the way! It also acts as malware protection for me. With the sandbox enabled, it blocks all nasties I can throw at it. Even tested Ransim against it and it blocks all the simulated ransomware.

Though I must point out that I got the ideal settings from someone quite knowledgeable about all things CF. Not sure if I can point you guys to some of her review vids, but they are quite helpful. I used to use binisofts paid product, but noticed that I can do all that it does on CF using the "custom ruleset" in the firewall options. Then it will ask before letting anything make a connection out and you can filter requests as you wish.

I have been running the free version of GlassWire for several weeks now - not as a stand alone firewall but in conjunction with my inbuilt Windows 10 firewall. Whilst it is generally not advisable to run two firewalls together GlassWire is designed to run along side the Windows firewall and provides considerable additional useful information and operates unobtrusively after a brief training period where the user vets connection alerts related to installed programs and apps.
Don't know what level of protection it would offer on its own but as an adjunct to Windows firewall it is an excellent and very user friendly tool which is being continually improved and developed (latest update yesterday).
I was somewhat sceptical of GlassWire initially because of the rather gimmicky colorful graphics but I am glad I tried it and it is a definite keeper on my computers.

GlassWire is only a firewall in the sense that it is a front-end to Windows Firewall. If you disable Windows Firewall then the GlassWire firewall features will also be disabled. Quite a few users don't touch the firewall features - I am one that doesn't - but it might be useful one day if I get a malware infection and want to use the firewall feature to block all network access.

I mainly use it as a system monitor to keep track of all applications and devices interacting with the network from my computer. Many people use it only for bandwidth monitoring as a lot of people have quotas on their Internet connection. If they want to monitor all their network traffic then they put it on every computer.

P.S. I adopted it when I first heard about it here. I liked it so much I've paid for a full version even though I only need the free features.

anyone have checked "GlassWire" yet?

Also, check out Windows Firewall Control from Binisoft (different software from Windows "10" Firewall Control).

Just FYI, Jetico Personal Firewall is now freeware as of April 13, 2016 for those of you in need of an excellent firewall w/ HIPS for Windows 8 and older...


Please, try and consider adding in list, another free firewall called "Free Firewall". I haven't used it, but I read good reviews about it.
Can be found here:

PS: Windows Firewall seems to be essential now for Windows 10, as if you disable it, you cannot receive automatic Windows updates o.O

While looking for a new firewall, I chose to go back to Comodo, which I have used in the past with good results. Bad move. While I had no technical errors or problems installing in Windows 10, the first thing I saw it install was Geek Buddy! I saw no option made available in install to not install this program. I am usually pretty good at catching this. I did catch where it wanted to change homepages and search engine.
So off the uninstall Geek Buddy - Not happening. Uninstall button was disabled in add/remove programs. So I uninstalled Comodo and guess what - it left Geek Buddy behind on my computer. Thankfully this time the uninstall button was enabled so I could get rid of it. Then scanned for leftovers just in case.
I would not have expected this from Comodo, so I will no longer consider it as an option anymore.

Although it has been a long time since I installed Comodo, I was sure there is an option to choose what to install, which for me always did not include the annoying GeekBuddy.

I honestly was on with PrivateFirewall, until in messed up a handful of my computers. The computer would start and it would give me a black screen. I looked it up and tried to fix it, but I never found a solution. Had to format my PC for that. Keep in mind I do not say something like "OMG THEIR PROGRAM DESTROYED MY PC! DEFINITELY A VIRUS! DO NOT INSTALL!". I usually laugh at people that exaggerate like that. But it did it 5 times, 3 being on my main PC.

I returned to Comodo mostly cause I am used to it and I know where to go and what to adjust to make it work. Just to check it out I just downloaded the installer of Comodo Internet Security. Seems the option is still there when you install it.

When the installer starts, on the bottom left there is a customize option. You click that and you can enable and disable what you want. I used to disabled only GeekBuddy in the past, but now I disable Chromodo too, since I use Comodo Dragon instead. But the option is still there to disable what you want.

Hi tim,
thanks for this very intreresting paper!
And what about "Sophos UTM Essential Firewall", free for home users? Did you tested it? I'd be quite glad to have your opinion about it.
Best regards

"You will need a dedicated computer to use Sophos firewall application"... so it is therefore outside the scope of this review. MC - Site Manager.

You're right... I didn't notice that! Thanks for answering so fast!

BEWARE FOR COMODO on windows 10! It gave me huge problems and difficulties to uninstall. After boot I only had a black screen, and couldn't run anything. I couldn't even get in safemode and it even gave me my first BSOD in windows 10. Had to use Linux to straighten things up. NOT FOR BEGINNERS.

Windows 10 firewall control has a very, very, very annoying sound, so uninstalled it straight away. Please, developers, get rid of that sound!

Zone-alarm is getting too little credit here. It's really a "fire-and-forget" kind of software, with more than enough possibilities if you want them.

Software always will give problems. That does not make them bad. Definitely Comodo always had and probably still have issues with BSODs and you can see so in their main site too. Obviously a lot of them happen because of conflicts though, rather than just the product. Of course updates do not happen without reason too.

I had a black screen problem with Private Firewall and not only once, but I remember it happened always when I did something specific. But either way, I have been using Comodo Internet Security for many years now and I do not get problems from it. It runs along MalwareBytes Antimalware with no problems and it is fine.

But I agree. Definitely not for someone that wants to start it up and forget it.

It is very easy to blame software for system problems that can be caused by a variety of other issues. I know plenty of folks using Comodo with Windows 10 and having zero issues. MC - Site Manager.

It's just intended as a big warning, not a blame. I recently installed Windows 10, and there's only some other securitysoftware there, like malwarebytes and bitdefender. Other firewalls didn't give any problems.