Best Mozilla Firefox ESR Alternatives in 2025

Looking for alternatives to Mozilla Firefox ESR? In this comparison, we take a closer look at Mozilla Firefox ESR alongside similar software solutions including Mozilla Firefox ESR, Waterfox, LibreWolf, Mozilla Firefox, Pale Moon, Zen Browser, Cent Browser and AntiBrowserSpy.

Our detailed comparison table highlights key features, pricing, and performance of these leading solutions, empowering you to make an informed decision. Whether you're seeking robust functionality, user-friendly design, or cost-effective alternatives, explore how Mozilla Firefox ESR, Waterfox, LibreWolf, Mozilla Firefox, Pale Moon, Zen Browser, Cent Browser and AntiBrowserSpy stack up to find the perfect software for your goals.

	Open Source	Privacy & Security Features	Customization & Extensions Support
Mozilla Firefox ESR	Free and open-source browser focused on long-term stability and security.	Enhanced privacy protections, long-term security support, less frequent updates to maintain stability.	Supports most Firefox add-ons; fewer updates may affect extension compatibility occasionally.
Waterfox	Open-source project based on Firefox code emphasizing user privacy and customization.	Emphasizes user privacy, blocks telemetry data, open-source without tracking.	Highly customizable with support for most Firefox extensions but lacking mobile version.
LibreWolf	Open-source Firefox fork with enhanced privacy and security features.	Strong privacy focus, blocks telemetry and trackers, includes additional privacy extensions.	Supports Firefox extensions and additional privacy-focused add-ons; may face some compatibility issues.
Mozilla Firefox	Free and open-source web browser with frequent updates and a wide range of features.	Strong tracking protection, anti-phishing, encryption, private browsing mode and regular security patches.	Wide variety of add-ons and customizable interface with regular feature updates.
Pale Moon	Open-source web browser derived from Firefox with focus on customization and legacy support.	Strong security emphasis with own security features but less frequent updates leading to slower bug fixes.	Highly customizable interface supporting selected Firefox add-ons but not all extensions work.
Zen Browser	Open-source, privacy-focused browser supporting Mozilla Add-ons with an active community.	Built-in ad blocking, tracker protection, HTTPS-only mode, integrated security tools for enhanced privacy.	Supports extensive add-ons from Mozilla's store with adjustable interface settings.
Cent Browser	Open-source web browser based on Chromium offering extensive customization features.	Includes built-in ad blocker and VPN functionality, aims for user privacy and low resource usage.	Offers extensive customization including mouse gestures, hotkeys, scrollable tabs, supports Chrome extensions.
AntiBrowserSpy	Paid software application not open source; focuses on privacy by cleaning browser data.	Protects privacy by cleaning tracking data across multiple browsers; no free version available.	No extension support; focuses on browser setting management for privacy protection.

Open Source

Mozilla Firefox ESR	Free and open-source browser focused on long-term stability and security.
Waterfox	Open-source project based on Firefox code emphasizing user privacy and customization.
LibreWolf	Open-source Firefox fork with enhanced privacy and security features.
Mozilla Firefox	Free and open-source web browser with frequent updates and a wide range of features.
Pale Moon	Open-source web browser derived from Firefox with focus on customization and legacy support.
Zen Browser	Open-source, privacy-focused browser supporting Mozilla Add-ons with an active community.
Cent Browser	Open-source web browser based on Chromium offering extensive customization features.
AntiBrowserSpy	Paid software application not open source; focuses on privacy by cleaning browser data.

Privacy & Security Features

Mozilla Firefox ESR	Enhanced privacy protections, long-term security support, less frequent updates to maintain stability.
Waterfox	Emphasizes user privacy, blocks telemetry data, open-source without tracking.
LibreWolf	Strong privacy focus, blocks telemetry and trackers, includes additional privacy extensions.
Mozilla Firefox	Strong tracking protection, anti-phishing, encryption, private browsing mode and regular security patches.
Pale Moon	Strong security emphasis with own security features but less frequent updates leading to slower bug fixes.
Zen Browser	Built-in ad blocking, tracker protection, HTTPS-only mode, integrated security tools for enhanced privacy.
Cent Browser	Includes built-in ad blocker and VPN functionality, aims for user privacy and low resource usage.
AntiBrowserSpy	Protects privacy by cleaning tracking data across multiple browsers; no free version available.

Customization & Extensions Support

Mozilla Firefox ESR	Supports most Firefox add-ons; fewer updates may affect extension compatibility occasionally.
Waterfox	Highly customizable with support for most Firefox extensions but lacking mobile version.
LibreWolf	Supports Firefox extensions and additional privacy-focused add-ons; may face some compatibility issues.
Mozilla Firefox	Wide variety of add-ons and customizable interface with regular feature updates.
Pale Moon	Highly customizable interface supporting selected Firefox add-ons but not all extensions work.
Zen Browser	Supports extensive add-ons from Mozilla's store with adjustable interface settings.
Cent Browser	Offers extensive customization including mouse gestures, hotkeys, scrollable tabs, supports Chrome extensions.
AntiBrowserSpy	No extension support; focuses on browser setting management for privacy protection.

Choosing the right software isn’t just about features. Size, license type, user ratings, and popularity also matter.

This quick comparison shows how Mozilla Firefox ESR stacks up against Mozilla Firefox ESR, Waterfox, LibreWolf, Mozilla Firefox, Pale Moon, Zen Browser, Cent Browser and AntiBrowserSpy in these key areas—helping you find the best alternative for your needs.

	Size	License	Popularity
Mozilla Firefox ESR	37.4MB	Open Source	12%
Waterfox	66.5MB	Commercial	0%
LibreWolf		Open Source	1%
Mozilla Firefox	43.4MB	Freeware	100%
Pale Moon	34.4MB	Freeware	0%
Zen Browser		Freeware	0%
Cent Browser	92.5MB	Freeware	0%
AntiBrowserSpy	9.3MB	Commercial	4%

Size

Mozilla Firefox ESR	37.4MB
Waterfox	66.5MB
LibreWolf
Mozilla Firefox	43.4MB
Pale Moon	34.4MB
Zen Browser
Cent Browser	92.5MB
AntiBrowserSpy	9.3MB

License

Mozilla Firefox ESR	Open Source
Waterfox	Commercial
LibreWolf	Open Source
Mozilla Firefox	Freeware
Pale Moon	Freeware
Zen Browser	Freeware
Cent Browser	Freeware
AntiBrowserSpy	Commercial

Rating

Mozilla Firefox ESR
Waterfox
LibreWolf
Mozilla Firefox
Pale Moon
Zen Browser
Cent Browser
AntiBrowserSpy

Popularity

Mozilla Firefox ESR	12%
Waterfox	0%
LibreWolf	1%
Mozilla Firefox	100%
Pale Moon	0%
Zen Browser	0%
Cent Browser	0%
AntiBrowserSpy	4%