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.
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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.
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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.
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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.
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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

Security Guides

Security Products

Inbound Vulnerability Tests

Outbound Vulnerability Tests

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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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Please rate this article: 

Your rating: None
Average: 4.3 (546 votes)


The current Windows firewall is in fact better than most third party alternatives unless of course you install untrusted software in which case nothing will protect you. It also depends on how you configure Comodo to work with other software. This is highlighted in many places including Wilders. MC - Site Manager.

I think the 3 star rating for Comodo is about right. Excellent protection but a nightmare to uninstall. Even if you follow Chiron's lengthy clean install guide (and how many average users are prepared to do all that?) there is still a good chance you will have serious issues, as I found, eventually having to ditch Comodo after numerous BSOD's and failure of V8 to install properly. Until Comodo rectifies this I don't think it can be recommended. Sure, there are other security products that don't always uninstall cleanly, but none I've used have been anywhere near as problematic as Comodo.

Used PrivateFirewall for a long time (on my Win XP), but now with Win 10 I gave up on 3rd party options. One thing that annoys me with Windows built in firewall is user unfriendly interface when you want to block connection for some specific file. Found one simple program that allows you to do that. The whole program has about 600 KB. You can even add option to explorer contex menu to block specific files from there. Program doesn't install, it's portable. You can start it from anywhere, but then it does copy itself with ini file to Windows Program Files section.

Can't add link, so try googling "Firewall App Blocker" by Sordum.

just a disapointment:
when I click on the link "Security Wizard" in the introduction, I'm given a message: OUPS§ NOT FOUND
In spite of the fact that the article is recent
hat's happen? Could you help?

Hi Camile, thanks for your comment. The security wizard has been discontinued from our site at this time. I invite you to visit our forum for any questions or comments you may have on selecting the appropriate security software

I'm surprised after reading the pros/cons for Comodo that it didn't get more stars. Sure it installs the AV files, but I can live with that if everything else is 5 stars. As for potential uninstall leaving remnants...most software does that anyways.

I've been using Private Firewall for several months now with good success. I find the popups quite handy as (being paranoid) I want to know exactly what programs and software are attempting to access the internet. I'd also give it a 5-star.

Hi MC! Hope all is well. Well I have to ask you if you have heard anything from or if you can contact Privacyware regarding a Windows 10 compatibility update. As you know there is a lot of people out there who love Privatefirewall, me included...which brings up another question for you, how can you disable trusted publishers in Windows 7 firewall? Reason is Qihoo is trying to force people to upgrade from 360 Internet Security to Total Security. Total Security, as you know is not the same product, however Total Security Essentials is. If I want to wait to see how Total Security Essentials develops before I decide to upgrade then I should be able to block the 360 Total Security Online installer rule 360 just made in windows 7 firewall. Correct?? Why is it everytime 360 updates its virus definitions it changes the 360 Total Security Online installer rule it made from "my blocked setting" to allow? As usual I thank you for your time and consideration and any links you can provide.

Hi darrin71. Management of trusted publishers is detailed here.

The two things that annoy me most are popup windows for "are you sure you really want to exit" and apps that overwrite permission rules. Regarding 360, I guess you're stuck with this behaviour because no doubt the permissions granted for the program at install are what allows it to overwrite your block rule. Although not an ideal solution for you maybe, but I would suggest switching to Panda until the full direction of the 360 products becomes more clear. I have Panda on two machines and neither have been compromised by anything nasty and what money I do have is still in my bank account. :D

Regarding Privatefirewall, I've sent a contact to the vendor and will post their response here as soon as I get it. MC - Site Manager.

I have now received a reply from Privacyware re: Windows 10 compatibility. Although this is possible, it is unlikely in the short term so you will need to use Windows own firewall (my recommendation) or find an alternative. MC - Site Manager.

Privacyware have now informed us of a workaround regarding Privatefirewall and Windows 10 which is working for the majority of those who have tried it.

Please let us know your own experience after trying this so we can pass this on to the developer. Naturally we need only constructive data to forward so please be sure to include your system details and any other relevant information. MC - Site Manager.

My installed firewall, Privatefirwall 7.0, has been disabled after I upgraded to Windows 10 Home. I tried uninstalling, downloading and reinstalling Privatefirewall 7.0 and it failed. I tried downloading the latest versions of Comodo Internet Security and ZoneAlarm Free Firewall, and Windows immediately stopped me from installing each of them and told me neither app was compatible with Windows 10.

I dug into the Security settings of Windows 10 and found the default Windows firewall already turned on. Why can't I install a TRUSTED firewall and not rely on Microsoft apps?

Did you run the compatibility check before you jumped on the upgrade?
There are very good reasons why Microsoft "knows better".
I believe we can only fret about them not allowing us to install certain pieces of software AFTER MS's own product of this kind has failed us.
As I wrote in #122798
"I am afraid that we hang on way too tenaciously to old paradigms. Yes, under Vista and earlier MS operating systems a third party firewall made sometimes sense - if the user could configure it. But nowadays?
If you can and want to tinker, be my guest. For the average Joe/June I have them stick with what is in Windows. "
It seems you ran against a "tinker"-wall instead a firewall.

I also think staying with Windows firewall is the best option. If you download the test report from this page it makes interesting reading, even though it relates to the Windows 7 firewall. MC - Site Manager.

The link at the end of paragraph 7 to "most important advice of all" is wrong/broken.

Besides this: 99% of my many thousands of customers are not able (or willing) to even do the least bit of configuration. They ALL have (so far) been served well by the Windows default FW.

I am afraid that we hang on way too tenaciously to old paradigms. Yes, under Vista and earlier MS operating systems a third party firewall made sometimes sense - if the user could configure it. But nowadays?

If you can and want to tinker, be my guest. For the average Joe/June I have them stick with what is in Windows.

Quick Selection Guide - Basic Firewalls seems details are not updated for Windows 7 Firewall Control....
it is now called windows 10 Firewall,
version is,
It is now Designed for Windows 10/8/7/Vista/2008/2012/XP/2003,
size is 4212 KB,

Online Armor has been quit:
It should probably be removed later (though you can still download the latest free version v7.0.0.1866 somewhere using google search) or atleast mentioned.

PrivateFirewalls latest version is from 19th December of 2013.

AVS Firewall also seem to have ceased to exist.

Thanks for the comment. Agree looks like Online Armor has ceased support and development, so while it's still available for download elsewhere I will probably move it to the unsupported section. Likewise for AVS firewall.

PrivateFirewall I believe the developer has not completely stopped development of the firewall; however, as far as I know they haven't been actively developing it either.

The list has been getting a bit outdated lately, over the next while I'll aim to refresh and update the list with some more current software. Stay tuned!

The home pages for Outpost Firewall Free and Online Armor Free could be updated.

Thanks MrBrian, Outpost links have been updated. Seems like Online Armor has now been discontinued though. I'll probably move those to a different discountinued section..might leave the reviews up though, since they're already there as like an 'FYI' for all the ones who want to explore

AVS Firewall isn't available at the link provided.

It was previously there but on a different page, looks like they have removed it completely now and discontinued the product. Thanks for bringing it to our attention I will make the necessary changes.

AVS firewall is still available from Softpedia and some other trusted download sites. MC - Site Manager.

There are 3 Security Wizard-related links that could be deleted. Also, the link for "Comprehensive List of Firewalls" could be updated.

Apologies for the delay in responding but thanks for the heads up. Will update accordingly

I have used the free version of Online Armor for several years and have been completely satisfied though I agree it is not for complete beginners. My point is that while I appreciate the difficulties of keeping things up to date your review is badly out of date; in particular it is wrong in saying that OA does not have automatic updates. The current version 6.0 does have them and they are entirely reliable. Your picture is of version 3 or 4 and even that had automatic updates though they were not always reliable.

I am quite surprised to see no mention of Windows Firewall Notifier ( is present here! I had come back to techsupportalert after a fresh install of Windows just to see if anything had changed since I had last installed a firewall. Nothing had changed unfortunately, so I snooped on MajorGeeks and found Windows Firewall Notifier. This, like TinyWall and Windows 7 Firewall Control, utilitzed the built-in windows firewall, but unlike the others, just seemed to work for me. No issues, no excessive popups, great performance and memory + CPU utilization, and to top it all off it's open source. This really should be the #1 recommendation for a basic firewall IMO. It allows the basic firewall to act as a two-way firewall, which is exactly what I needed. Once installed, it blocks all outbound requests by default and a simple popup is displayed above the system tray allowing you to Allow/Block as expected. I highly recommend giving it a shot.

Also worth a mention is Binisoft's "Windows Firewall Control" ( (I know, painfully similar to Sphinx Software's Windows 7/8 Firewall Control which IS already mentioned here). It looks like it performs similarly and from the screenshosts seems well-designed. I am just too happy with Windows Firewall Notifier at the moment but if I didn't like it I would definitely give this a shot.

I also want to briefly mention my gripes with TinyWall and Windows 7/8 Firewall Control here just for the record.

TinyWall sounded like the best frickin' idea ever when I read the description here. I loved how light it was, the premise was so promising. However, it continually seemed to deny access for all applications unless I turned it on the mode that allows all traffic. Even configuring specific rules never seemed to alleviate the "no internet access" problem, so eventually, after continually turning off the firewall, I gave up and moved to Windows 7 Firewall Control.

Windows 7 Firewall Control, unlike TinyWall, actually works as expected. It performs amicably, however there is one thing that sucks about it and it really just drove me crazy. Sometimes, for example when viewing flash content on a web page, Windows 7/8 Firewall Control would trigger a pop-up asking to allow/block the "System" app that is flash. This "System" dialog would also pop-up with Windows services intermittently as well. That's all fine and dandy, that's what it's intended to do, right? However, Windows 7/8 Firewall Control will inform you on trying to "Allow" that you need to upgrade to the Premium version to actually allow handling of "System" apps. Seems like an arbitrary destinction to nag you to pay. I get it, the developer made a good program and wants to get paid, but IMO this app didn't perform well enough to justify paying to stop this nagging.

The biggest thing I like about Windows Firewall Notifier is that on top of performing how I want, it's open source. No nagging!

Good luck in your searches all.

Finally I should mention I tried Private Firewall. It worked decently enough, but was more than I needed (I really wanted just a better way to utilize the Windows Firewall). It didn't seem to hurt performance but I suspected it was a bigger impact than the other programs I mentioned which all utilized the built-in firewall. It also just looks like it was designed in the '80s, heh, and unfortunately that matters to me. More importantly, for my needs, I don't want to have to become familiar with a slew of crazy firewall options that I'll likely never need that might only result in unexpected behavior. The KISS mentality. I'd order the average users' options like this:

1. Windows Firewall Notifier
2. Private Firewall
3. Windows 7/8 Firewall Control
4. Tinywall