List of the Top 20 Free Firewall Software in 2025

Enforza offers a robust cloud firewall solution designed for enterprise needs, utilizing an innovative network security platform. Our technology converts Linux instances into powerful firewall appliances featuring in-depth packet inspection. Key Features: • Stateful inspection for Layer 4-7 firewall defense • Tailored rule creation with protocol-specific filtering options • Enhanced NAT functionalities, including SNAT and DNAT • Enforcement of security policies across VPC/VNET environments • Minimal latency impact, measured in sub-milliseconds Enforza simplifies the firewall setup process while outperforming traditional cloud-native options. Experience effective firewall protection without incurring the data processing charges associated with services like AWS Network Firewall, Azure Firewall, and NAT Gateways. Secure your cloud infrastructure in no time. For detailed technical specifications, visit enforza.com/firewall.

Keep an eye on the data usage of each application on your computer with GlassWire's detailed network monitoring graph, which allows you to review both sent and received data over time while identifying the connections your PC is making. It effectively identifies spyware, malware, poorly behaving applications, and bandwidth-intensive programs, enabling you to block their connections using its robust firewall. You can also oversee all devices connected to your network and receive notifications when unfamiliar devices attempt to access your WiFi. Additionally, GlassWire alerts you to any network-related modifications to your computer or unusual alterations in your applications that may suggest the presence of malware, ensuring your system remains secure. This comprehensive monitoring helps you maintain control over your network environment and safeguard against potential threats.

Cloudflare serves as the backbone of your infrastructure, applications, teams, and software ecosystem. It offers protection and guarantees the security and reliability of your external-facing assets, including websites, APIs, applications, and various web services. Additionally, Cloudflare secures your internal resources, encompassing applications within firewalls, teams, and devices, thereby ensuring comprehensive protection. This platform also facilitates the development of applications that can scale globally. The reliability, security, and performance of your websites, APIs, and other channels are crucial for engaging effectively with customers and suppliers in an increasingly digital world. As such, Cloudflare for Infrastructure presents an all-encompassing solution for anything connected to the Internet. Your internal teams can confidently depend on applications and devices behind the firewall to enhance their workflows. As remote work continues to surge, the pressure on many organizations' VPNs and hardware solutions is becoming more pronounced, necessitating robust and reliable solutions to manage these demands.

NextDNS provides extensive protection against a variety of security threats by efficiently blocking ads and trackers on websites and apps, all while ensuring a safe and monitored internet experience for children across all devices and networks. You have the ability to evaluate your security requirements and personalize your protection by enabling more than ten distinct safety features. By integrating trustworthy threat intelligence feeds that encompass millions of malicious domains and are continually updated, you can significantly fortify your defense strategies. Our system surpasses conventional tracking methods by analyzing DNS queries and responses in real time, which facilitates the rapid detection and prevention of harmful activities. Since there is often a narrow timeframe of just hours between the registration of a domain and its potential use in an attack, our sophisticated threat intelligence framework is specifically designed to identify harmful domains more effectively than conventional security measures. Furthermore, by utilizing the most popular ad and tracker blocklists that feature millions of constantly updated domains, you can successfully eliminate ads and trackers from both websites and applications, including the most advanced ones. In summary, NextDNS equips users with the necessary tools to create a customized and safer browsing environment that meets their individual security needs, thereby enhancing overall online experience.

IPFire is a robust and secure Open Source firewall operating on the Linux platform. It is designed with a user-friendly interface, offering outstanding performance in various settings and flexibility that accommodates a diverse user base. Focusing on security as its primary goal, IPFire is built to protect against online threats while also ensuring that your network is shielded from potential breaches. The firewall features a powerful engine along with an integrated intrusion prevention system, both of which collaborate effectively to defend your network against cyber attacks and denial-of-service incidents. Created as free software through the efforts of a collaborative community, IPFire enjoys the confidence of hundreds of thousands of users around the world. Its main objective is to deliver maximum security while allowing for straightforward configuration to set up a firewall that efficiently prevents unauthorized access. IPFire's default configuration organizes the network into separate zones, such as LAN and DMZ, each equipped with specific security policies that facilitate effective risk management and enable tailored configurations to meet unique needs. This intentional architecture significantly boosts the overall security of any network utilizing IPFire, providing peace of mind to its users.

The pfSense initiative offers a cost-free network firewall solution, built upon the FreeBSD operating system and featuring a tailored kernel. Additionally, it encompasses various third-party open-source software packages. Thanks to its package management system, pfSense can deliver functionalities that rival or exceed those of standard commercial firewalls, all without any imposed restrictions. As a result, it has supplanted numerous leading commercial firewalls in installations worldwide, such as those from Check Point, Cisco PIX, Cisco ASA, and Juniper, demonstrating its growing popularity and reliability in the cybersecurity landscape. This shift reflects the increasing trust users place in open-source solutions for their network security needs.

Conventional packet filters are slowly losing relevance as the trend shifts towards Next-Generation Firewalls, even among open-source solutions. Among these, OPNsense emerges as a prominent choice, offering features such as intrusion detection, application management, web filtering, and antivirus protection. Every network, regardless of scale, faces threats; even devices in domestic settings, like smartwatches and washing machines, are vulnerable and require strong security protocols. Firewalls are essential components of a holistic security approach, providing protection against both traditional and novel threats. To ensure a firewall's effectiveness, it is crucial to have a thorough understanding of its features, make sure it is user-friendly, and position it strategically within the network. OPNsense meets these vital criteria through various functionalities, making it a formidable solution. This book is designed to be an essential resource for those interested in grasping, installing, and configuring an OPNsense firewall efficiently. By delving into the complexities of OPNsense, users can significantly enhance their digital security posture. Additionally, the insights provided will empower individuals to navigate the evolving landscape of cybersecurity with confidence.

UltraDNS is a powerful, cloud-driven authoritative DNS service tailored for enterprises, offering dependable and rapid query responses for websites and vital online assets. This fully managed DNS solution ensures total website availability while integrating cutting-edge security measures for heightened protection against online threats. As global users increasingly seek seamless and secure digital experiences, the intricacies of DNS management have surged dramatically. The growth of Internet of Things (IoT) devices and the proliferation of various cyber threats have posed significant challenges for organizations aiming to create a robust DNS strategy that meets their IT needs. It has become progressively more challenging to sustain a skilled in-house team dedicated to DNS management, and acquiring the necessary resources to develop a cohesive strategy that addresses today's Internet challenges can often be impractical. With UltraDNS, you can guarantee that your website and digital assets are consistently accessible, as the service is backed by a promise of 100% uptime and exceptional service-level agreements across a global platform. This unwavering commitment allows businesses to concentrate on their core activities, all while relying on the expertise of professionals who expertly manage their online presence. By leveraging UltraDNS, organizations can navigate the complexities of DNS while ensuring their digital infrastructure remains resilient and responsive to evolving demands.

Xvirus Firewall is designed as a user-friendly solution that enables individuals to oversee all active connections and effectively manage access rights. Through an uncomplicated method, it makes use of whitelisting and blacklisting techniques to control connections. However, it does not offer configurable options or sophisticated features for assessing connection validity. This straightforwardness appeals to novices while still delivering adequate functionality for seasoned users. Whether one prefers to install it and run it in the background or customize the settings for a tailored experience, Xvirus Firewall ensures strong security in either case. Additionally, with the aid of Xvirus' Network Monitor, users can retrieve extensive details regarding their application's connections, such as protocol, IP address, port number, connection status, and process ID. By regulating which applications can function on their systems, Xvirus Firewall empowers users to take charge of their security. Its easy-to-navigate rules list allows users to quickly identify which programs to permit or block, resulting in a hassle-free security management process. Ultimately, Xvirus Firewall achieves a harmonious blend of accessibility and control, positioning itself as an essential tool for anyone aiming to bolster their system’s security while also being capable of adapting to their specific needs. With its intuitive interface, users can feel confident in their ability to maintain a secure environment without the need for extensive technical knowledge.

Guardian provides a dependable and secure solution for protecting your privacy and data while engaging with apps and browsing the web on your iOS device. By directing traffic through its firewall servers, Guardian effectively hides your IP address from the sites you access, making it more challenging for advertisers to monitor your activities. It employs robust AES-256 encryption to safeguard your passwords, financial information, and other sensitive data, rendering it nearly impossible for hackers to breach your security, regardless of your location. Alongside this strong encryption for all outgoing traffic, Guardian also eliminates unwanted junk, thereby improving your mobile surfing experience. You can safely allow permissions for certain applications on your device, assured that any attempts to send data to unauthorized trackers will be efficiently blocked. Moreover, Guardian prevents unwanted connections from various trackers, including those that monitor your location, emails, and generic data, creating a more secure online environment. This all-encompassing protection not only secures your privacy but also enables you to explore the digital landscape with confidence and tranquility. With Guardian, you can enjoy the internet while knowing that your personal information is well-guarded against potential threats.

The Android Firewall is crafted for immediate deployment, providing strong defenses against hacker attacks while notifying you each time an application tries to send data online. You will be able to see which apps are connecting to different servers and using your mobile data. With easy-to-use filtering options, you can choose to allow or block specific app connections. This firewall empowers you to effectively manage and prevent unwanted data traffic. Additionally, you have the option to completely restrict an app's access to the internet. The AI-enhanced Android firewall protects you from unauthorized intrusions by recognized intelligence agencies and governmental bodies. Our built-in Intrusion Prevention System (IPS) proactively blocks all known servers and IP addresses linked to organizations such as the FBI, CIA, NSA, and GCHQ, thereby adding an extra layer of security. If there is an attempt to reach these restricted entities, you will receive a specific notification. Furthermore, Firewall AI protects you from surveillance servers based in nations like China, Iran, and Russia, as well as threats from mobile tracking, ensuring that your privacy is preserved and secure. In an age where data breaches are becoming more frequent, this firewall stands as a vital resource for anyone who prioritizes their online safety and wishes to navigate the digital landscape with confidence. It is not just a security tool; it represents a commitment to personal privacy and data protection.

Comodo Advanced Endpoint Protection offers a stellar anti-malware suite that meticulously protects your servers, workstations, laptops, and netbooks, while also providing advanced, real-time monitoring and management of crucial system resources. It can function as a complete security solution or as a standalone sandbox to boost existing antivirus programs, making Comodo ESM a leading option for endpoint defense on Microsoft Windows systems, including servers, desktops, laptops, and tablets. The full Comodo Endpoint Security suite features five layers of protection—Antivirus, Firewall, Host Intrusion Prevention, Auto-Sandbox, and File Reputation—operating at the user level right on the desktop. Its cutting-edge auto-sandbox technology effectively blocks malware infections and prevents damage to the operating system by running untrusted processes in a controlled environment. Additionally, Comodo's endpoint security is uniquely recognized as the only managed anti-malware solution that includes a limited warranty of $5,000 against malware infections, reinforcing its dedication to user security. By merging these advanced functionalities, Comodo ensures users benefit from a strong and dependable defense against the ever-changing landscape of cyber threats, instilling confidence in their digital safety.

Sophos UTM takes threat prevention to new and impressive levels. At the heart of Sophos Sandstorm lies an advanced deep learning neural network, a sophisticated form of machine learning that proficiently recognizes both known and unknown malware without relying on conventional signatures. Importantly, Sophos UTM 9.4 is among the first products to integrate our cutting-edge next-gen cloud sandboxing technology. Sandstorm significantly boosts defenses against ransomware and targeted assaults while offering extensive visibility and analytical tools. It promptly and accurately identifies evasive threats before they can penetrate your network. Additionally, it provides remarkable value by delivering enterprise-grade protection without the hassle of high costs or complexities. You can enhance the security of your web servers and Microsoft Enterprise Applications against cyber threats while ensuring secure access for external users through reverse proxy authentication. Our innovative all-in-one solution also offers complete SMTP and POP message protection against spam, phishing attacks, and data breaches, which significantly elevates your overall cybersecurity strategy. In summary, Sophos UTM empowers organizations with powerful tools to effectively protect their digital assets and maintain a strong security posture. With these capabilities, businesses can confidently navigate the ever-evolving landscape of cyber threats.

Google Cloud firewalls are deeply woven into the fabric of cloud networking, providing both scalability and precision tailored to meet the unique security needs of your organization. They offer a flexible and customizable framework, enabling you to enforce security measures at different tiers, such as organization, folder, and project, while granting you adaptable control over your firewall rules and policies. Moreover, your security management can be significantly enhanced through features that provide visibility and optimization, delivering critical insights into firewall rule usage and identifying potential improvement areas. In addition, by utilizing network tags and service accounts, you can create detailed controls that effectively oversee both north-south and east-west traffic, ensuring that comprehensive security is maintained throughout your network. This comprehensive strategy not only strengthens your security posture but also streamlines the management of your cloud infrastructure, making it easier to adapt to evolving security challenges. Ultimately, this robust approach empowers businesses to operate confidently in a secure cloud environment.

Open-source software combined with a universal router plays a crucial role in making network access more equitable for all. VyOS aims to transform the way individuals connect to networks, empowering them to create the solutions they envision without facing constraints, limitations, or exorbitant costs. We assert that access to the internet is as vital for human progress as essential resources like food, water, air, and healthcare. Founded by engineers with a passion for innovation, VyOS stands as an open-source company dedicated to facilitating unrestricted network access without financial barriers. Our mission is realized through VyOS, leveraging our open-source software and virtual platforms to provide robust solutions. We offer features such as stateful firewalls, zone-based firewalls, and various types of NAT, including one-to-one, one-to-many, and many-to-many configurations. Moreover, our commitment extends to transparency, allowing users to engage in auditing, create customized images, and contribute to the development, with full access to the entire codebase and build toolchain available to all. This collaborative approach not only enhances security but also fosters a community of innovation and shared knowledge.

m0n0wall represents a dedicated effort to create an all-encompassing embedded firewall software that, when used with an embedded PC, offers a full range of essential functionalities commonly found in commercial firewall appliances, all while being user-friendly and available at no cost as free software. The initiative is built on a streamlined version of FreeBSD, integrating a web server, PHP, and various utilities, with the configuration for the entire system stored in a single XML text file to promote ease of understanding and simplicity. Remarkably, m0n0wall may be the first UNIX-based platform to utilize PHP for its boot-time configuration, departing from the conventional reliance on shell scripts, and it distinctly organizes all system settings in XML format, highlighting its innovative stance in firewall technology. This unique approach not only improves both the usability and management of the system but also signifies a notable progression in the field of open-source firewall solutions. Furthermore, m0n0wall stands as a testament to the capabilities of free software, demonstrating that robust security solutions can be accessible to all without the burden of financial constraints.

Bit Guardian Firewall is an all-encompassing security solution designed to provide users with a secure and smooth online surfing experience. It proactively protects against harmful content by detecting and blocking malicious URLs while also filtering out unwanted applications and websites. Thanks to its built-in ad-blocking functionality, users can enjoy browsing without interruptions from distracting or potentially dangerous ads. Additionally, it safeguards user privacy by reducing online tracking, allowing individuals to visit their favorite sites without fear of surveillance. To enhance its security measures, the firewall utilizes Avira's extensive malware databases, establishing a strong defense against both online and offline threats. This firewall software is specifically tailored for compatibility with Windows operating systems and is produced by Bit Guardian GmbH, a well-respected software development company based in Gräfelfing, Germany. Its consistent updates and customer support make it a compelling choice for anyone seeking to strengthen their digital security. Ultimately, Bit Guardian Firewall stands out as an essential tool for users who prioritize safety and privacy in their online activities.

Azure Firewall is a comprehensive, cloud-managed network security solution that aims to protect the assets within your Azure Virtual Network. Functioning as a fully stateful firewall, it boasts built-in high availability and infinite scalability specifically designed for cloud infrastructures. By implementing Azure Firewall, you can effortlessly simplify both the deployment and management of your network security measures while guaranteeing strong protection for your critical resources. This service allows you to create, enforce, and track connectivity policies for applications and networks across multiple subscriptions and virtual networks. Moreover, with Azure Firewall, you can centralize security management across all virtual networks, employing a cohesive set of application and network rules to boost security oversight. This unified approach not only simplifies management tasks but also significantly strengthens your network's overall defense mechanisms, making it a vital tool for any organization operating in the cloud. In today’s digital landscape, the importance of robust network security cannot be overstated, and Azure Firewall plays a crucial role in achieving this.

CrowdSec is a collaborative and open-source intrusion prevention system that not only analyzes behavioral patterns but also effectively responds to attacks while sharing valuable intelligence within its community. With a larger presence than cybercriminals, it empowers users to develop personalized intrusion detection systems by employing behavioral scenarios to detect potential threats. Users can take advantage of a crowdsourced and curated cyber threat intelligence platform to enhance their security measures. Additionally, you can specify the types of remediation actions you want to implement and utilize the community's IP blocklist to automate your protective strategies. CrowdSec is versatile and can be deployed on various platforms, including containers, virtual machines, bare metal servers, or even directly through our API. By working together, our cybersecurity community is actively dismantling the anonymity of cybercriminals, which is a significant advantage we hold. Contributing to this effort is easy, as you can share IP addresses that have caused you trouble to help build and maintain an effective IP blocklist for everyone’s benefit. Notably, CrowdSec's capability to process extensive logs is remarkably efficient, outperforming Fail2ban by a factor of 60, which makes it an indispensable tool in the fight against cyber threats. Through collective effort and shared intelligence, we can create a safer digital environment for all users.

AP Lens serves as a Sandbox browser that enhances network security through DNS Whitelisting, effectively thwarting attacks before they infiltrate your systems. What advantages does AP Lens provide? Web Filtering: Offers a versatile and intuitive way to block unwanted content. Anti-Phishing: Eliminates the risk of similar-looking domains with complete accuracy. Ransomware Defense: Shields your network from cybercriminals while ensuring business applications remain unaffected. Secure Remote Work: Implements VPN technology to uphold internet usage policies. AP Lens Augmented Whitelist: A solution to eliminate 0-Day Attacks. Compliance: Adheres to the regulatory standards required by cybersecurity insurance policies. One-Click Installation: Eliminates the hassle of user setup or updates on their computers. No Maintenance: Prevents malware and phishing threats without the need for continuous oversight. With over two decades of collective expertise in cybersecurity, cloud security, and information protection, our team has successfully served various sectors, including both private and public domains, ensuring robust protection for all clients.