Our verdict: ZoneAlarm Free Firewall replaces the simple on/off feel of Windows Firewall with two-way monitoring, per-program internet access control and extra layers such as anti-bot and early boot protection. It works alongside Microsoft Defender but not alongside other antivirus products, and Check Point promotes its paid suites to free users.
About ZoneAlarm Free Firewall
ZoneAlarm is Check Point's consumer security brand and one of the oldest personal firewalls for Windows. The free firewall monitors incoming and outgoing traffic, decides which programs may access the internet, hides the PC from port scans and lets you classify your home network as a private zone and untrusted Wi-Fi as a public zone.
On top of that it adds Advanced-Access Protection against attacks such as raw data access and SCM and COM tricks, Component Control against malicious DLLs injected into trusted programs, Early Boot Protection against rootkits and an anti-bot module. Updates install automatically. It needs Windows 10 or 11, 3 GB RAM on 32-bit or 4 GB on 64-bit systems, 1.5 GB of disk space and .NET Framework 3.5 or later, which the installer adds if missing.
What it does well
- Two-way firewall. Monitors incoming and outgoing traffic and blocks unwanted connections.
- Program control. Decides which applications are allowed to access the internet.
- Network zones. Treats home networks as private and unknown networks as public with stricter rules.
- Anti-Bot. Detects and blocks bots that try to use the PC in botnets or reach malicious sites.
- Early Boot Protection. Checks during startup that a trusted operating system, not a rootkit, is loading.
Who it is for
Good fit
Users who want visible control over which programs connect to the internet, beyond Windows Firewall.
Look elsewhere
People who use a third-party antivirus, since ZoneAlarm only supports running next to Microsoft Defender.
Pros and cons
Pros
- Free two-way firewall with program control
- Public and private network zones
- Anti-bot and early boot protection included
- Updates itself automatically
Cons
- Not compatible with antivirus products other than Microsoft Defender
- Upgrade offers for paid ZoneAlarm suites
- Heavier than Windows Firewall, with 1.5 GB disk space required
How to install ZoneAlarm Free Firewall
The button downloads ZoneAlarm's official online installer, which fetches the rest during setup. Uninstall any other anti-malware software first; Check Point states ZoneAlarm is only compatible with Microsoft Defender. Watch each setup screen for offers of paid ZoneAlarm products or extra components and untick what you do not need.
Questions about ZoneAlarm Free Firewall
Is ZoneAlarm Free Firewall free?
Yes. ZoneAlarm Free Firewall is free to download and use; Check Point sells paid suites such as ZoneAlarm Extreme Security NextGen with more protection.
Does ZoneAlarm Free Firewall include antivirus?
No. It is a firewall; ZoneAlarm Free Antivirus is a separate free product. Check Point states the firewall is compatible only with Microsoft Defender as the antivirus.
Does ZoneAlarm work on Windows 11?
Yes. Check Point lists Windows 10 and Windows 11 as supported.
