Alternatives to LuLu
Free open source Mac firewall
LuLu ranks #3 of 7 in Firewall software, with an Alt Score of 65. It is licensed under GNU General Public License v3.0, donationware from Free and available on macOS. 9 of 9 checklist rows are verified against a public source.
Privacy-conscious macOS users and security-minded admins who want visibility into which applications are phoning home, including protection against malware command-and-control traffic and unwanted data exfiltration.
A free, open-source firewall that alerts on and blocks unknown outgoing network connections. You can approve or deny connections as they happen, build rules by program or remote endpoint (with wildcard/regex support), import or export rule sets, and run in standard (alerting), passive (silent), or block-all modes. It also supports allow/block lists from local or remote sources, VirusTotal lookups, code-signing checks, and a built-in network monitor (Netiquette).
LuLu runs as a macOS System Extension using the Network Extension framework (not a kernel extension) to intercept outgoing connections in real time, then permits or denies each one based on user-defined or automatically generated rules.
Where LuLu stands out
Verified capabilities most alternatives don't have.
Why people leave LuLu
Dashed reasons are sourced facts; the rest are opinions. Vendors can dispute.
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Ranked alternatives
Ordered by Alt Score. Click any score to see the breakdown.
Feature comparison
Rows come from the Firewall software checklist (13 rows). Human-verified cells only. ? means the value has not been verified.
| Firewall software checklist | LuLu | pfSense | NetGuard | Little Snitch | GlassWire | OPNsense |
|---|---|---|---|---|---|---|
| Pricing model | ||||||
| Starts at | ||||||
| License | ||||||
| Platforms | ||||||
| Outbound connection alerts | ||||||
| Per-app rules | ||||||
| Network-wide (router / gateway) | ||||||
| Profiles (home, public) | ||||||
| Open source | ||||||
| One-time purchase option | ||||||
| Traffic monitoring UI | ||||||
| IDS/IPS | ||||||
| Low overhead |
Every fact and feature listed for LuLu is verified against its own pages. Each alternative is sourced on its own page.
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Pricing model Donationware verified 2026-07-09
Free; README links to Patreon for support donations.
LuLu is a free, open-source firewall that blocks unknown outgoing connections, protecting your privacy and your Mac.
https://objective-see.org/products/lulu.html -
Platforms macOS verified 2026-07-09
v4.3.2 · macOS 10.15+
https://objective-see.org/products/lulu.html -
License GNU General Public License v3.0 verified 2026-07-09
GNU GENERAL PUBLIC LICENSE Version 3, 29 June 2007
https://api.github.com/repos/objective-see/LuLu/license -
Starts at Free verified 2026-07-09
LuLu is a free, open-source firewall
https://objective-see.org/products/lulu.html -
Status active verified 2026-07-09
updated: 2026-07-09, archived: False
https://api.github.com/repos/objective-see/LuLu -
Outbound connection alerts Yes verified 2026-07-09
LuLu's purpose is to alert you anytime a new (unauthorized) outgoing network connection is created.
https://objective-see.org/products/lulu.html -
Per-app rules Yes verified 2026-07-09
enter the path to the program … Then, enter the remote address or domain, remote port, and finally select 'Block' or 'Allow'. Click 'Add' to add the rule, which will be persistently saved
https://objective-see.org/products/lulu.html -
Network-wide (router / gateway) No verified 2026-07-09
Host-based macOS application firewall; installs on individual Macs only.
LuLu only monitors outgoing traffic
https://objective-see.org/products/lulu.html -
Profiles (home, public) Yes verified 2026-07-09
Recently profiles were added to LuLu (v4.0+). A profile defines a set of rules and settings.
https://objective-see.org/products/lulu.html -
Open source Yes verified 2026-07-09
LuLu is the free open-source macOS firewall
https://github.com/objective-see/LuLu -
One-time purchase option No verified 2026-07-09
Entirely free; optional Patreon donation.
LuLu is a free, open-source firewall
https://objective-see.org/products/lulu.html -
Traffic monitoring UI Yes verified 2026-07-09
click the 'Network Monitor' menu option in LuLu's status bar menu... This will launch Objective-See's Netiquette, a network monitor application, that has been packaged into LuLu.
https://objective-see.org/products/lulu.html -
IDS/IPS No verified 2026-07-09
Firewall only; no intrusion detection/prevention engine.
LuLu is a free, open-source firewall that blocks unknown outgoing connections
https://objective-see.org/products/lulu.html -
Low overhead Partial verified 2026-07-09
Uses Apple's Network Extension framework; no explicit overhead benchmark.
LuLu leverages Apple's new Network Extension framework.
https://objective-see.org/products/lulu.html
FAQ
Yes. NetGuard, GlassWire and Portmaster have a free tier or are fully free. Free-tier limits in the comparison table are verified and dated.
pfSense, NetGuard and OPNsense — every license claim links its source.