Company lists · Data refreshed September 2026
Top 25 Appsec companies based in the United States
RevenueBase identified 3,230 appsec companies headquartered in the United States as of September 2026 and tracks 93,834 professional contacts across them, including 41,488 with verified work emails. San Francisco is the largest hub.
This list covers appsec companies headquartered in the United States, matched on what each company actually does as described in its own words. Ranked by team size, largest first. Every row shows the company's own description, its RevenueBase Smart Search rating, and when it was last checked. Data refreshed September 21, 2026.
Published by RevenueBase, a B2B data infrastructure company. This list was built with RevenueBase Smart Search, the natural-language company search RevenueBase customers use to build their own targeted lists and unlock verified emails and direct dials at the companies on them. How these lists are built and judged.
The 25 largest appsec companies based in the United States
Ranked by team size| # | Company | Contacts | |||
|---|---|---|---|---|---|
| 1 | 14,289 contacts → | ||||
Indirect evidence “Fortinet makes possible a digital world that we can always trust through its mission to protect people, devices, and data everywhere.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 2 | 6,058 contacts → | ||||
Indirect evidence “HackerOne is a global leader in Continuous Threat Exposure Management (CTEM) and the only solution provider that pairs the simultaneous trust of the Fortune 500 and the world's…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 3 | 3,649 contacts → | ||||
Indirect evidence “We are a crowdsourced security company that safeguards organizations' assets from sophisticated threat actors before they can strike-by uniting our customers with trusted hackers…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 4 | 3,302 contacts → | ||||
Indirect evidence “CyberArk is the global leader in Identity Security.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 5 | 3,058 contacts → | ||||
Indirect evidence “Qualys, Inc.(NASDAQ: QLYS) is a leading provider of disruptive cloud-based security, compliance and IT solutions with more than subscription customers worldwide, including a…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 6 | 1,669 contacts → | ||||
Indirect evidence “BeyondTrust is the global cybersecurity leader protecting Paths to Privilege™.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 7 | 1,252 contacts → | ||||
Indirect evidence “Thales is a global leader in cybersecurity, helping the most trusted organizations in the world protect their most critical applications, data, and identities anywhere at scale.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 8 | 1,232 contacts → | ||||
Indirect evidence “GuidePoint Security provides trusted cybersecurity expertise, solutions, and services that help organizations make informed decisions and minimize risk.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 9 | 1,217 contacts → | ||||
Indirect evidence “On Dec.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 10 | 1,188 contacts → | ||||
Indirect evidence “Snyk, the leader in secure AI software development, empowers organizations to build fast and stay secure by unleashing developer productivity and reducing business risk.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 11 | 1,187 contacts → | ||||
Indirect evidence “Black Duck® meets the board-level risks of modern software with True Scale Application Security, ensuring uncompromised trust in software for the regulated, AI-powered world.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 12 | 1,059 contacts → | ||||
Indirect evidence “WatchGuard® Technologies, Inc.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 13 | 1,042 contacts → | ||||
Indirect evidence “Checkmarx helps the world’s largest enterprises get ahead of application risk without slowing down development.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 14 | 904 contacts → | ||||
Indirect evidence “ZeroFox is the solution to discover, validate, and disrupt external cyber threats before they harm revenue or reputation.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 15 | 874 contacts → | ||||
Indirect evidence “Trustwave, a LevelBlue Company, is a globally recognized cybersecurity leader that reduces cyber risk and fortifies organizations against disruptive and damaging cyber threats.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 16 | 844 contacts → | ||||
Indirect evidence “Today’s threatscape is relentless.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 17 | 813 contacts → | ||||
Indirect evidence “The Synack Red Team is a private freelance security research team that spans 6 continents and over 80 countries.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 18 | 641 contacts → | ||||
Indirect evidence “At Network Intelligence, we combine our team of 500+ security professionals with Transilience – our cutting-edge AI platform.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 19 | 629 contacts → | ||||
Indirect evidence “Telos Corporation (NASDAQ: TLS) empowers and protects the world’s most security-conscious organizations with efficient, adaptable, and secure solutions that safeguard people…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 20 | 628 contacts → | ||||
Indirect evidence “VikingCloud delivers battle-tested cybersecurity and compliance solutions that simply work.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 21 | 587 contacts → | ||||
Indirect evidence “NetSPI® pioneered Penetration Testing as a Service (PTaaS) and leads the industry in modern, continuous pentesting.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 22 | 566 contacts → | ||||
Indirect evidence “Comodo - Protecting Your Digital World At Comodo, we are dedicated to safeguarding your digital property with Comodo Website Security.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 23 | 552 contacts → | ||||
Indirect evidence “Veracode is a global leader in Application Risk Management for the AI era.” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 24 | 535 contacts → | ||||
Indirect evidence “Funded by world-class investors, including Evolution Equity Partners, Silver Lake Partners, Sequoia Capital, GV, Riverwood Capital, and others, SecurityScorecard is the global…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
| 25 | 523 contacts → | ||||
Indirect evidence “UltraViolet Cyber is the only security operations partner that unifies red, blue, and purple team capabilities into one integrated program, finding what's vulnerable, stopping…” Source: RevenueBase Database · checked Sep 21, 2026Thanks. The Data Team will review it. | |||||
RevenueBase Smart Search
RevenueBase Smart Search assesses information from a company’s LinkedIn profile, information supplied directly by the company, its website, and other publicly available sources. It uses that information to rate how closely the company relates to this list’s category: appsec companies. Every row carries its rating and the description the rating was read from, so each one can be checked rather than taken on trust.
- Strong evidence
- The company's own public description of its business names appsec companies.
- Partial evidence
- Its own public description names part of appsec companies, so it works in or next to the category without describing itself that way.
- Indirect evidence
- The description shown does not name appsec companies. The match rests on the rest of the company's public profile rather than the one sentence quoted here, so this is the rating to check first.
RevenueBase Smart Search is how these lists are built: RevenueBase's data engine and AI assemble the companies that match a category defined in a user's own words, so a list can be about what companies actually do rather than about whichever industry code they were filed under.
Showing 25 of 3,230 appsec companies based in the United States
See the full list, filter by size, metro and specialty, and get verified emails and direct dials for all 41,488 reachable decision-makers.
Free signup · no credit card
Appsec companies based in the United States at a glance
As of Sep 21, 2026Companies by employee count
Email recency for this list is measured worldwide rather than for United States, so it is reported there. Company counts and contact totals on this page are exact for United States, over 3,230 companies.
How this list was built
Company categories are rarely black and white. RevenueBase reads each company's own description of its business to decide whether it belongs among appsec companies, so some rows will be adjacent to the category rather than pure plays. The description and RevenueBase Smart Search rating on every row are there so you can check each match yourself.
- Source
- The RevenueBase company graph: 60 million companies and 398.9 million professional contacts resolved from primary sources, queried with RevenueBase Smart Search, the natural-language company search available to every RevenueBase user.
- What qualifies
- Companies headquartered in the United States whose own description of what they do matches “appsec companies”. Matching reads each company's description, not its industry code or its name.
- RevenueBase Smart Search
- RevenueBase Smart Search is how this list is assembled and how each row is rated. RevenueBase's data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to a category defined in a user's own words. Each row is rated strong evidence (its own description names appsec companies), partial evidence (it names part of the category) or indirect evidence (the description shown names none of it and the match rests on the rest of the company's profile). The description supporting each rating is quoted on the row.
- What we exclude
- Companies whose own description does not clearly place them among appsec companies, and records with no verified work email. Companies headquartered outside United States are excluded even when they keep an office there.
- Match quality
- In blind human judging of this matching method, 86% of matched companies were on target. Expect roughly 1 in 7 rows to be adjacent to the category rather than a pure play. Every row shows the company's own description and its RevenueBase Smart Search rating so you can judge each match yourself. Read the full methodology: how the lists are built, how the judging worked, and what the figure means.
- Ranking
- Team size, largest first: companies are ordered by the number of professionals RevenueBase tracks at each one. Employee ranges shown are reported bands, for context.
- Verification
- Every listed company carries at least one verified work email, 41,488 across the full list. Contacts re-verify on a rolling cadence, and each contact's own verification date is shown inside RevenueBase.
- Refresh
- This page's figures were pulled from the company graph on September 21, 2026. Lists refresh periodically as the graph is re-checked.
- Corrections
- Wrong category, wrong headquarters, or a company that has closed? Use “Report an issue” on any row. Reports go to the RevenueBase Data Team and feed back into the company graph.
Appsec companies by metro
- Appsec companies in San Francisco145
- Appsec companies in New York123
- Appsec companies in Austin93
- Appsec companies in Dallas53
- Appsec companies in Atlanta49
- Appsec companies in Chicago49
- Appsec companies in Miami47
- Appsec companies in Houston42
- Appsec companies in Los Angeles42
- Appsec companies in Seattle40
- Appsec companies in Boston38
- Appsec companies in Washington37
- Appsec companies in San Diego35
- Appsec companies in Denver33
- Appsec companies in Wilmington30
- Appsec companies in Arlington29
- Appsec companies in Tampa28
- Appsec companies in Charlotte27
- Appsec companies in Columbia27
- Appsec companies in Dover27
- Appsec companies in Sheridan26
- Appsec companies in San Jose25
Frequently asked
What is RevenueBase Smart Search?
RevenueBase Smart Search is how RevenueBase decides which companies belong on this list and how strongly each one fits. Its data engine and AI assess a company's LinkedIn profile, information supplied directly by the company, its website and other publicly available information, then relate it to the category the list is about. Each row is rated strong evidence when the company's own description names appsec companies, partial evidence when it names part of the category, and indirect evidence when the description shown names none of it and the match rests on the rest of the company's profile.
How many appsec companies are there based in the United States?
RevenueBase identified 3,230 appsec companies headquartered in the United States as of September 2026, matched on each company's own description of what it does rather than its industry code.
What is the largest company on this list?
Fortinet, headquartered in Sunnyvale, tops this list with the largest team on record.
Which city has the most appsec companies?
San Francisco leads with 145 headquartered companies, followed by New York (123) and Austin (93).
How do I get contact information for these companies?
A free RevenueBase account lets you run this exact search and work the top results, verified emails and direct dials included. Upgrading unlocks all 41,488 verified decision-maker contacts tracked across these 3,230 companies.
How current is this list?
The list refreshes periodically as the company graph is re-checked. This page's figures were pulled on September 21, 2026.
Ready to reach these companies? Verified emails and direct dials for all 3,230 appsec companies based in the United States. Start with a free account, no credit card.
Download this list →Related lists
Appsec companies by geography
- Appsec companies based in Calgary, Canada
- Appsec companies based in Montreal, Canada
- Appsec companies based in Ottawa, Canada
- Appsec companies based in Toronto, Canada
- Appsec companies based in Ahmedabad, India
- Appsec companies based in Bangalore, India
- Appsec companies based in Bengaluru, India
- Appsec companies based in Chennai, India
- Appsec companies based in Hyderabad, India
- Appsec companies based in Mumbai, India
- Appsec companies based in New Delhi, India
- Appsec companies based in Noida, India
Browse the directory
About this data
RevenueBase is a B2B data infrastructure company. Its company graph covers 60 million companies and 398.9 million professional contacts, with emails verified on a rolling cadence rather than scraped once and left to decay. These company lists are generated directly from that graph with RevenueBase Smart Search, the same natural-language company search every RevenueBase user has: describe a market in plain words, get the companies that match, and add verified emails and direct dials for the people at them. It is the same data that powers RevenueBase's B2B data products, and a free account includes 500 credits to start. How these lists are built and judged.
More company lists
- All company lists
- Lists by location
- Lists A-Z
- New lists
- Appsec companies based in Calgary, Canada
- Appsec companies based in Montreal, Canada
- Appsec companies based in Ottawa, Canada
- Appsec companies based in Toronto, Canada
- Appsec companies based in Ahmedabad, India
- Appsec companies based in Bangalore, India