Top 7 Free Firewalls

John Ferguson
August 20, 2021
IT & Development

Top 7 Free Firewalls

Firewalls are among the most common form of digital security, alongside antivirus software. Since firewalls monitor traffic packets to and from a network and block malicious content, they’re well suited to foiling hackers. Many systems come with a prebuilt firewall. For instance, many wifi routers have basic hardware firewalls. There are also build-in software firewalls in many operating systems, like Windows. Given these measures, some may question how necessary a separate firewall is in their situation. These default protections may be enough for personal use.

There are many cases where additional security is recommended, or even required. For instance, any business user should have more robust firewall protections. Determined attackers can often breach default protections. Businesses, and others with sensitive data like financial information, are often their targets. This also includes personal contractors and freelancers, who interact with other businesses’ data. For these users, there is often much more financial and legal risk from malware and intrusion. Separate firewall software dramatically reduces this risk. 

What Kind of Firewall Do I Need?

In some cases, paid firewall products are a necessity. This is most often the case for larger businesses and enterprises. For these organizations, paid firewalls offer more security and customization. They are also often bundled with other security measures that larger organizations need. 

Paid offerings can also be overkill for some users. For smaller use cases and organizations, free firewall software may be ideal. Free firewalls reduce the up-front expense from security. They often rely on users to actively manage the firewall. Businesses that use free firewalls should have someone in-house who can manage the system. 

Free firewalls can also be more challenge to research and select. We’ve collected the best free firewalls to simplify this process. We’ll highlight each product profiles’ capabilities, advantages, and drawbacks. We’ll also identify any ideal use cases or reviewer feedback. 

The Top 7 Free Firewalls

1. Sophos XG Firewall Home Edition

Sophos XG Firewall is a leader in the firewall market. Its paid offering focuses on  more robust business use cases. Sophos also offers a free version of the platform tailored to home network use. The Home Edition offers web filtering, antivirus, and VPN connections, among other features. Home Edition also gives you more granular control over your network traffic and bandwidth usage. This gives users better network performance. 

Sophos XG Home Edition stands out for its wide range of features in a free product. While its designed for home users, it can also be viable for very small business users with lightweight network requirements. It also supports other Sophos appliances, and gives you an easy upgrade path if your needs scale up. 

There are some drawbacks to be aware of. For instance, the firewall requires a dedicated PC to run. It will overwrite any existing OS and files on a computer upon install. This means users should have a separate PC dedicated to running this firewall alone. The software is also capped at using 4 cores and 6 GB of RAM, so users may run into scalability problems over time. 

Sophos XG Firewall Home Edition is ideal for small use case power users. These users require paid-tier functionality, and have the extra hardware on-hand to support it. However, they lack the budget for up-front or  subscription costs. Sophos’s offering is perfect for users in this situation. 

2. ZoneAlarm Free Firewall

ZoneAlarm is a very popular firewall and anti-virus solution from Check Point. It offers a free version, which makes money via ads. There is also an ad-free Pro version with more capabilities. It is known for its ability to block viruses as well.

ZoneAlarm’s free version stands out for its excellent antivirus engine. It also offers more advanced options that are attractive to personal users. For instance, users can get identity protection features and mobile firewall protection for free. The identity and personal data protection features are particularly unique.

Unfortunately, the free version is still noticeably limited. For instance, it lacks 24/7 customer support and more advanced granular firewall controls. It’s also vulnerable to exploit attacks. for some users, ads-based monetization may be a deal-breaker.

ZoneAlarm is best for more casual users that appreciate the prebuilt bells and whistles. Not all users want, or need granular customization. Many have also become used to ads in everything. For these users, free identity and data protection make ZoneAlarm a compelling option. 

3. AVS Firewall

AVS is a legacy free firewall offering. It specializes in more granular visibility into web traffic and application connections. It also offers a popup blocker, firewall rule personalization, and traffic shaping. 

AVS stands out for its high level of customizability. The program splits into different modules, allowing users to focus on the features they need. The visibility AVS provides into network traffic is also excellent. 

There are also several drawbacks to be aware of. The most significant concern is the lack of consistent support for the firewall. The firewall can go years between official updates. This places the maintenance burdens on users more than others on this list. The firewall install also comes with an unusually heavy footprint. For instance, it requires downloading a separate secure browser with a firewall. The extra pieces are removable after the fact, but require extra steps.

The AVS firewall is best for users that value a high degree of customization and granular traffic control. It’s also ideal if you don’t care about the more modern bells and whistles. The personal control AVS affords administrators is great, especially if they want parental controls. 

4. OpenDNS Home

OpenDNS, backed by Cisco, offers free and paid versions of its firewall. It offers two free packages. One delivers broad firewall capabilities, while the other filters adult content. 

OpenDNS is a unique service on this list. It is cloud-based, rather than downloading software on-premise. Instead, it adjusts the router to route all traffic through the OpenDNS server. This delivers “edge service” protection, which is unusual among free products. This model also provides additional protection against attacks like DDoS. 

There are several advantages this model poses. For one, it protects all devices on the network by default. More important, it doesn’t need dedicated on-premise hardware. It offers good customization and alerts, but with minimal resource overhead. 

There’s also a tradeoff to using an edge service. All traffic gets routed through an OpenDNS server. This cedes control over your data and traffic to a 3rd party service. Privacy-conscious users may have issues with this lack of data control. Since everything gets routed elsewhere, internet performance may also be impacted.

5. Privatefirewall

PrivateFirewall is a technically discontinued free firewall that is still downloadable from 3rd party hosts. It serves both as a firewall and a host-based intrusion prevention system. This second function monitors the computer’s logs to identify flagged events. These events include unusual or malicious activities. It also protects logs from external tampering. 

PrivateFirewall has fallen out of use for many users, but there are still some benefits. Since it lacks many more modern features, it’s relatively easy to learn and configure. The safelist and blocklist functions are pretty straightforward and easy to use with a simple click. 

The lack of ongoing vendor support is a significant drawback to this firewall. In addition to lacking more modern features, it also has a more outdated UI and feel to it. Beyond this issue, the firewall also requires administrative privileges to save changes. This can cause complications for devices/networks with more than one user. 

PrivateFirewall is ideal for users that want something easy to set up and only occasionally update. It’s also best for single users that don’t have much prior experience. Setting up and managing PrivateFirewall is less likely to overwhelm anyone.

6. GlassWire

GlassWire has risen in market awareness as a free firewall and network security solution. It is designed for home or small business use. Its firewall capabilities rely upon the native Windows firewall (Defender), with additional alerting for suspicious behaviors. Notably, GlassWire offers several paid packages. These packages pay more attention to business users than most other freemium firewalls. The product’s network monitoring also enables traffic throttling features. The paid features include more network monitoring, additional logs history, and more scalability for SMBs. 

GlassWire stands out for being very easy to use. It boasts a very clean, simple, modern interface. This can be a significant advantage for casual users. The program doesn’t sacrifice detail for simplicity. It offers lots of detailed network information as well. 

Simplicity can come at the cost of functionality. GlassWire has relatively limited capabilities compared to some of its other modern peers. The depth of network information can also be a double edged sword. This amount of information can overwhelm some users if they don’t need it. Much of the scalability, especially across multiple PCs, is also paywalled. 

GlassWire is best for users that prioritize ease of use and simplicity in their firewall and network monitoring. This is particularly applicable for users that expect a modern graphical interface. 

7. Comodo Free Firewall

Comodo offers a Free Firewall, in addition to a paid security suite. Its free product features a sandbox environment, which is unique on this list. The sandbox allows users to test untrusted applications in a safe environment. The product also includes host intrusion protection and a secure browser, as well as an ad blocker. 

The Comodo firewall presents several unique advantages to users. The sandbox environment is a wholly unique offering among free products. Comodo also supports their firewalls with an updated thread database. Comodo also offers more advanced configurability, such as easy-to-use port security. 

On the other hand, Comodo is not simply “plug and play.” The firewall does need configuring. It also requires more of a learning curve to make the best use of the cooler features, like sandboxing. Comodo also requires users to download the extra programs beyond the firewall. Users can delete these features after the fact. 

Comodo Free Firewall is great for novice users looking to work with riskier programs. If users are downloading multiple applications of questionable or unknown origins, the sandbox is essential.  

Key Security Products to Protect your Business

Evolving security risks require more complex security protections. Whether you choose to adopt a free or a paid firewall, it should not be your only line of defense.

Businesses and professional users should also consider additional security options. A virtual private network (VPN) is an excellent tool for protecting your data and identity in transit. There are also many tools for securing your email environment. These tools include secure email gateways and email encryption tech. Organizations and individuals alike should also explore endpoint security tools for the mobile-first world. You can also check out our breakdown of the top antivirus solutions below.

About the Author

John Ferguson
John is a Research Associate at TrustRadius, focusing on content development and buyer-guided research. His goal is to support and enable better software buying decisions, with an eye towards helping people from all backgrounds navigate the world of business software. He has a BA in Politics from Centre College.

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