Comodo Free Firewall

Comodo's award-winning firewall
protects you from the viruses, malware, and hackers.

User Rating
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4.6 / 5 of 75 Reviews

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Comodo Firewall

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.

Release Details:

April 2, 2014. Please see latest release notes

CNET Editors' Choice

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

Comodo Firewall Awards:

SI Award Log SI Excellent Award SI Good Choice Award
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System Requirements:

Windows 7 / Vista / XP SP2 / Windows 8, 152 MB RAM / 400 MB space

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Marco POLO
Comodo Firewall Site

Hi, It would be nice if you mentionned what version number is offered to download on your site. Thanks for your attention

Looks great

I'm using Comodo's free firewall for a while now and I assure you this is a very good software that guarantees a policy-based control that takes care of security when you are online.

Customisable firewall

Superb firewall embedded with a strong prevention-based mechanism. Offers in-built security features, blocks unsafe URLs, and helps to manage web traffics.

Khloe Kristoffer
Wonderful firewall

I'm just here to add my two cents about what a wonder tool Comodo Firewall really is. The program has easy to follow and implement features, with a wide variety of customizable services. No wonder CNET gave it an editor's choice award. That's well deserved!

Kes Kirk
Better than Windows

This is better than Windows firewall application. Comodo is the best workstation software firewall solution in the market.

Important Firewall Features

Default Deny Protection™

Makes sure that only known PC-safe applications execute

Prevention-based security

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

Auto Sandbox Technology™

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

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

Cloud based Behavior Analysis

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

Cloud based Whitelisting

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

Game Mode

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

Application Control

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

Automatic updates

Stay current with the latest protection.

Precise and specific alert system

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

Easy to configure

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

Detailed summary screen

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

Uncluttered, user-friendly interface

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

Thorough security "wizards"

Preset security settings for simple point-and-click setup

Exclusive access to Comodo's "safe-list"

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.

'Training Mode' lets Firewall automatically create 'allow' rules

Firewall software learns your trusted programs to minimize alerts

Get the most from Firewall with Comodo Internet Security Pro 8

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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.

Sounds like Default Deny is important.

It is. DDP™ grants you, the user, ultimate control of what's granted access to a PC.

Will programs run OK in the Sandbox?

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.

How Firewall Works?

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.

But I'm not making every decision, right? I couldn't handle that.

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.

And how is Comodo Free Firewall software different from the dozens of other firewalls out there?

Our firewall software is the only true firewall protection operating with Default Deny Protection™ technology to ensure your computer's security.

Do programs stay in the Sandbox forever?

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.

OK, but what if a file I don't recognize asks for access?

Our free firewall contains detailed alerts letting you know the severity of the threat, and the type of file asking to execute.

Get the most from Firewall with Comodo Internet Security Pro 8
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When downloading the software you will also
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Technical support:

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.

Online Help Guide

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

Forum & Knowledgebase

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.
Read the Forum