Nessus VS Qualys
As of 4 November 2026, Qualys is named by 477 companies and Nessus by 610; Nessus skews to companies under 200 people (44% vs 31%), Qualys to companies over 1,000 (46% vs 31%).
As of 4 November 2026 · refreshed daily · counts move as websites, DNS and career sites are re-read.
The website-and-DNS footprint is not comparable between a marketing suite and a CRM: Nessus's script and mail records show on hundreds of thousands of small sites, Qualys rarely leaves a trace outside its own apps. Compare on the job-posting numbers; use the footprint for reach.
- Nessus: 2–200 employees
- 44%
- Qualys: 2–200 employees
- 31%
- Nessus: 1,000+ employees
- 31%
- Qualys: 1,000+ employees
- 46%
- Postings per company, 90 days
- 3.0 · 2.2
- Website or DNS footprint
- 0 · 0
Who chooses which
Share of each tool's companies in every segment. "Leans" marks a gap of more than two points.
| Segment | Nessus | share | Qualys | share | Leans |
|---|---|---|---|---|---|
| Self-employed | 17 | 3% | 10 | 2% | even |
| 2-10 employees | 36 | 6% | 29 | 6% | even |
| 11-50 employees | 86 | 14% | 44 | 9% | Nessus |
| 51-200 employees | 149 | 24% | 77 | 16% | Nessus |
| 201-500 employees | 84 | 14% | 48 | 10% | Nessus |
| 501-1000 employees | 48 | 8% | 49 | 10% | Qualys |
| 1001-5000 employees | 83 | 14% | 89 | 19% | Qualys |
| 5001-10000 employees | 27 | 4% | 29 | 6% | even |
| 10,001+ employees | 80 | 13% | 102 | 21% | Qualys |
| Segment | Nessus | share | Qualys | share | Leans |
|---|---|---|---|---|---|
| Technology & software | 296 | 49% | 184 | 39% | Nessus |
| Business & finance services | 116 | 19% | 130 | 27% | Qualys |
| Manufacturing & industry | 85 | 14% | 44 | 9% | Nessus |
| Consumer services & leisure | 27 | 4% | 14 | 3% | even |
| Public, community & associations | 22 | 4% | 16 | 3% | even |
| Utilities & infrastructure | 21 | 3% | 20 | 4% | even |
| Media & content | 11 | 2% | 10 | 2% | even |
| Commerce & trade | 9 | 1% | 21 | 4% | Qualys |
| Property & construction | 7 | 1% | – | – | outside top 12 |
| Transport, logistics & rental | 6 | 1% | 10 | 2% | even |
| Health care | 4 | 1% | 5 | 1% | even |
| Automotive | 3 | 0% | 7 | 1% | even |
| Hospitality & travel | – | – | 10 | 2% | outside top 12 |
| Segment | Nessus | share | Qualys | share | Leans |
|---|---|---|---|---|---|
| United States | 426 | 70% | 282 | 59% | Nessus |
| United Kingdom | 24 | 4% | 50 | 10% | Qualys |
| India | 20 | 3% | 6 | 1% | Nessus |
| France | 15 | 2% | 18 | 4% | even |
| Canada | 9 | 1% | 16 | 3% | even |
| Germany | 9 | 1% | 15 | 3% | even |
| Brazil | 7 | 1% | 9 | 2% | even |
| Belgium | 6 | 1% | 4 | 1% | even |
| Italy | 6 | 1% | 4 | 1% | even |
| Singapore | 6 | 1% | – | – | outside top 12 |
| United Arab Emirates | 5 | 1% | – | – | outside top 12 |
| Poland | 5 | 1% | – | – | outside top 12 |
| Australia | – | – | 6 | 1% | outside top 12 |
| Netherlands | – | – | 4 | 1% | outside top 12 |
| Spain | – | – | 3 | 1% | outside top 12 |
| Segment | Nessus | share | Qualys | share | Leans |
|---|---|---|---|---|---|
| IT operations & business systems | 1,892 | 79% | 1,014 | 74% | Nessus |
| Software engineering | 125 | 5% | 95 | 7% | even |
| Engineering (non-software) | 66 | 3% | 13 | 1% | even |
| Product, program & project management | 16 | 1% | 23 | 2% | even |
| Customer service & success | 13 | 1% | 11 | 1% | even |
| Data & AI | 11 | 0% | 4 | 0% | even |
| Education & training | 9 | 0% | 3 | 0% | even |
| Legal, compliance & risk | 8 | 0% | 8 | 1% | even |
| Skilled trades and field service | 8 | 0% | – | – | outside top 12 |
| Facilities cleaning and security | 7 | 0% | 4 | 0% | even |
| Unclassified | 7 | 0% | – | – | outside top 12 |
| Quality, safety & environment | 6 | 0% | 1 | 0% | even |
| Finance & accounting | 5 | 0% | 1 | 0% | even |
| Sales | 4 | 0% | 28 | 2% | even |
| Administration & office | 2 | 0% | – | – | outside top 12 |
| Construction and civil | 2 | 0% | 4 | 0% | even |
| General management & consulting | 1 | 0% | 3 | 0% | even |
| Marketing & communications | 1 | 0% | 3 | 0% | even |
The companies behind each column
Companies using Nessus →
Companies using Qualys →
vulnerability management ranked →
Quote the sentence with the date and the link. The numbers change daily; the link always shows the current ones.
Qualys is named by 477 companies in job postings and Nessus by 610; 228 name both. (Breaknorm, 4 November 2026, https://breaknorm.co/compare/nessus-vs-qualys)
Read from the source, not self-reported
Every number on this page can be traced to a page we crawled or a posting we read. Full methodology →
- Job postingsRead hourly from career sites. A tool counts when the employer's own text names it as the team's system; both tools can count for one company.
- Website and DNSScripts and embeds on the company's pages, plus SPF, DKIM, MX and CNAME records of its domain that point at the vendor.
- SegmentsCountry, size and industry from the company profile built from its website.
- Not a reviewNo ratings, prices or feature claims. For those, read the vendors.
Nessus vs Qualys: questions
Which is more used, Nessus or Qualys?
By companies naming it in their own job postings, Nessus (610) over Qualys (477). By website-and-DNS footprint, Qualys (0 vs 0), because its scripts and mail records sit on many small company sites.
Who chooses Nessus?
44% of Nessus companies have 2 to 200 employees, against 31% for Qualys. 31% of Nessus companies have over 1,000 employees, against 46% for Qualys.
Do companies run both?
228 companies name both in their postings, usually Nessus in marketing and Qualys in sales, or during a migration.
Where do these numbers come from?
From the employer's own text in job postings read hourly from career sites, and from scripts found on company websites in our crawl. No vendor data, no surveys.
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