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Download World's #1 Free Firewall that finds threats and protects your PC

  • Fast and hassle-free online experience
  • Manages traffic on your PC
  • Blocks all Internet attacks
  • Secures all connections when you are online
  • Monitors in/out connections

CNET Editors' Choice, 5-Star Rated

Comodo Firewall Pro introduces the next evolution in computer security: Default Deny Protection (DDP™). What is DDP? Most security programs maintain a list of known malware, and use that list to decide which applications and files shouldn't access a PC. The problem here is obvious. What if the list of malware is missing some entries, or isn't up to date?

DDP fixes this problem to ensure complete security. The firewall references a list of over two million known PC-friendly applications. If a file that is not on this safe-list knocks on your PC's door, the Firewall immediately alerts you to the possibility of attacking malware. All this occurs before the malware infects your computer. It's prevention-based security, the only way to keep PCs totally safe.

5 top secrets why Comodo Firewall is different

  • No complex configuration Issues — perfect for amateur users
  • Quickly learns user behavior to deliver personalized protection
  • User-friendly, attractive graphical interface
  • Lots of configuration options let techies configure things just as they like
  • DDP-based security keeps you informed and PCs safe

Important Firewall Features

Firewall Protection DEFAULT DENY

Makes sure that only known PC-safe applications execute


Stops viruses and malware before they access your computer…so it isn't too late to stop them.

Sandbox Technology Auto Sandbox

The sandbox is a virtual operating environment for untrusted programs - ensuring viruses and other malicious software are completely isolated from the rest of your computer

Personalized Alerts PERSONALIZED

Firewall remembers which software is allowed to operate and changes its alerts accordingly.

Cloudbased Analysis CLOUD BASED

Cloud based behavior analysis system detects zero-day malware INSTANTLY.

Cloudbased Whitelisting CLOUD BASED

Cloud based whitelisting of trusted publisher easily identifies a safe file and vendor


Suppresses operations that could interfere with a user’s gaming experience such as alerts, virus database updates or scheduled scans.

Application Control APPLICATION

Provides users with the ability to lockdown their PC so only known good applications can run.

Automatic Updated AUTOMATIC

Stay current with the latest protection.


Warnings specify the level and type of possible threat from each source.

Configure Easy EASY TO

Tell the free firewall to scan upon installation and add all current applications to the safe-list.


Easily access an at-a-glance snapshot of current security settings

User friendly Interface UNCLUTTERED,

Quickly navigate through the various parts of Firewall protection without getting lost


Preset security settings for simple point-and-click setup


List of over two million known PC-friendly files and apps. Provides free firewall protection with the knowledge to let safe files and apps run.


Firewall software learns your trusted programs to minimize alerts

Firewall Software Frequently Asked Questions

What's a Firewall?

Firewall protection is a batch of security measures for your PC, designed to keep malware, viruses, and hackers at bay.
Firewall is network security software, programmed to prevent illegal access that travels in and out of a private network. It helps to manage the incoming and outgoing traffic of network that is based on a specific set of protocol. It examines each an every activity and blocks if it does not meet the required security norms.
No – the sandbox is the first part of a trust decision engine. After an unknown application has been placed in the sandbox, Internet Security will also automatically queue it for submission to Comodo labs where it will be analyzed by our technicians. If it is found to be harmless then it will be added to the global safe list that will be downloaded by all Internet Security users in the next round of updates. Once it is added to the safe list, the application will no longer be run in the sandbox by Internet Security. If it is found to be malicious then it will be added to Comodo's list of malware signatures and will be deleted after the next round of updates.
It is. DDP™ grants you, the user, ultimate control of what's granted access to a PC.
Not at all! Our free firewall software has access to Comodo's safe-list of over two million known PC-friendly applications. When one of them accesses your PC, the firewall won't bother you because there's no reason to worry.
Our free firewall contains detailed alerts letting you know the severity of the threat, and the type of file asking to execute.
Yes. Applications in the sandbox are run under a carefully selected set of privileges and will write to a virtual file system and registry instead of the real system. This means untrusted (but harmless) applications have the freedom to operate as usual while malicious programs are prevented from accessing or infecting your computer. This provides smoothest and most secure user experience possible.
Our firewall software is the only true firewall protection operating with Default Deny Protection™ technology to ensure your computer's security.
Yes. However, enterprises looking to implement Internet Security on large networks of workstations would benefit from the centralized management capabilities of Comodo Advanced Endpoint Security.

Need help with your Comodo products? We're here to help, anytime 24/7

When downloading the software you will also receive access to a GeekBuddy expert, available 24/7. Click on Chat Now from your Management Interface or click on the GeekBuddy icon on your desktop.and vendor.

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Make sure to have your order number or subscription information available.

For technical product questions visit our Support Home Page click on the "Submit a Ticket" link and select "Internet Security Support" from the dropdown menu and submit.

Check out our Online Help Guide for tips on how to use and configure our products and for detailed technical information.

Go to the Help Guide

Our Forum is populated with fellow Comodo users and developers alike and can quite often be the quickest and friendliest way to find answers to questions that you have.

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System Requirements

Microsoft® Windows® XP 32bit, Vista/Win7/Win8/Win8.1/Win10
32 or 64-bit, 150 MB RAM
400MB of available hard-disk space

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