KnowBe4 vs Tenable Nessus: Complete Comparison (2026)
Choosing between KnowBe4 and Tenable Nessus is a common decision for cybersecurity buyers in 2026. Tenable Nessus has been in the market since 2002, giving it a 8-year head start over KnowBe4 (founded 2010). KnowBe4 serves 65K+ orgs users while Tenable Nessus has 43K+ orgs users globally. KnowBe4 differentiates with phishing simulations and security training, while Tenable Nessus leads with vulnerability scanning and compliance checks. In this head-to-head comparison, KnowBe4 earns a higher hiltonsoftware.co score of 92/100 — but the right choice depends on your specific needs, budget, and team size.
Quick Comparison
Feature-by-Feature Comparison
Pros & Cons at a Glance
After comparing KnowBe4 and Tenable Nessus across features, pricing, and user satisfaction, KnowBe4 takes the lead with a score of 92/100 versus Tenable Nessus's 90/100. KnowBe4's key advantages include "best-in-class phishing simulations" and "huge training content library". That said, Tenable Nessus has its own strengths — particularly "industry standard vulnerability scanner" — making it a viable alternative for specific use cases.
Neither KnowBe4 nor Tenable Nessus offers a free plan. KnowBe4 starts at $18/user/yr and Tenable Nessus at $2790/yr. For the investment, KnowBe4 delivers phishing simulations and security training, while Tenable Nessus provides vulnerability scanning and compliance checks.
Bottom line: Choose KnowBe4 if you need companies training employees to recognize and avoid phishing attacks. Go with Tenable Nessus if your priority is security teams running regular vulnerability assessments across all it assets. Both are strong cybersecurity tools — we recommend trying a trial of each before committing.
Companies training employees to recognize and avoid phishing attacks.
Security teams running regular vulnerability assessments across all IT assets.