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Snort vs Security Onion: catalog facts
Snort	Security Onion
Free Free and open source under the GPL. Subscriber rule sets are paid.	Freemium The platform is free, while Onion AI features are offered through sales representatives.
Windows, Linux, Self-hosted	Linux, Self-hosted
Mature rule language and a large body of community and vendor rules Runs in detection or inline prevention mode	Complete monitoring platform installed from a single ISO Includes packet capture, detection rules and threat hunting
Rule tuning is required or the alert volume is unusable The subscriber rule set, with the newest rules, is paid	Needs dedicated hardware or virtual machines and setup time Onion AI details are only available through sales
Downloadable app	Self-hosted, Operating system
Open source	Closed source
License: GPL-2.0	License not stated
Not stated if an account is needed	Not stated if an account is needed
Not stated if it works offline	Not stated if it works offline
Official website Full listing and sources Checked September 22, 2026	Official website Full listing and sources Checked September 23, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.