CISO Tribune

Vendor comparison · 2 companies

Prompt Security vs Promptfoo

Prompt Security offers protection for both employee use of AI tools and the apps an organization builds. Promptfoo builds open-source tools for secure, reliable AI applications. CISO Tribune files both under AI firewalls and guardrails and AI model and agent security. This page sets the two records side by side: what each sells, where it is based, who owns and funds it, the customers it names and its recent news, each fact numbered to its source.

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  • Prompt Security
  • Promptfoo
Prompt Security vs Promptfoo: Products, Customers and Funding Compared
Prompt SecurityPrompt Security offers protection for both employee use of AI tools and the apps an organization builds.prompt.securityPromptfooPromptfoo builds open-source tools for secure, reliable AI applications.promptfoo.dev
What it sells
  • Prompt Fuzzer[4]An open source tool for AI vulnerability assessment.
  • Red Teaming[2][4][5]Simulates real users to uncover application-specific vulnerabilities.
  • Evaluations[2][5]LLM evaluation of prompts and models that can run inside CI workflows.
Categories
Headquarters
Not stated on its pagesSan Francisco, United States[1][3]
Founded
2023[1]2024[1][12]
Ownership and funding
Owned by SentinelOne since 2025[3][7][8][10]Owned by OpenAI[12]
Named customers
Not stated on its pagesNot stated on its pages
Recent news
Not stated on its pages
  • March 9, 2026OpenAI agreed to buy Promptfoo, a startup helping businesses find and fix security issues in AI models during development.[13]
  • March 9, 2026OpenAI announced it has acquired Promptfoo, an AI security startup founded in 2024 to protect LLMs from adversarial attacks.[12]
G2 and Gartner Peer Insights
  • G2: listed, seen November 10, 2026[10]
  • Gartner Peer Insights: Not stated on its pages
  • G2: Not stated on its pages
  • Gartner Peer Insights: Not stated on its pages
Who it fits
Not written yetNot written yet
Last verified
September 27, 2026November 4, 2026

Where they overlap

  • Prompt Security and Promptfoo are both filed under AI firewalls and guardrails and AI model and agent security.

Where they differ, field by field

  • Prompt Security's primary category is AI firewalls and guardrails; Promptfoo's is AI model and agent security.
  • Prompt Security is also filed under Workforce AI usage security. Promptfoo is also filed under Static application security testing and Breach simulation and automated pen-testing.
  • Prompt Security lists Prompt Fuzzer. Promptfoo lists Red Teaming and Evaluations.
  • Promptfoo is headquartered in San Francisco, United States.
  • Prompt Security was founded in 2023. Promptfoo was founded in 2024.
  • Prompt Security is owned by SentinelOne, since 2025. Promptfoo is owned by OpenAI.

What it sells: Prompt Security

What Prompt Fuzzer does[4]
Prompt Fuzzer is listed under AI Security Tools on the Prompt Security site. The site describes it as an open source tool for AI vulnerability assessment.

What it sells: Promptfoo

What Red Teaming does[2][4][5]
Promptfoo creates thousands of context-aware attacks tailored to the customer's application. The open-source Community version includes up to 10k probes per month at no charge.
What Evaluations does[2][5]
Promptfoo's LLM evaluation can be integrated into a CircleCI pipeline. Promptfoo can be integrated with test frameworks like Jest and Vitest to evaluate prompts as part of existing testing and CI workflows. Promptfoo provides real-time alerts and automated evaluations to show LLM security status across all projects.

Questions about Prompt Security and Promptfoo

What do Prompt Security and Promptfoo sell?
Prompt Security sells Prompt Fuzzer. Promptfoo sells Red Teaming and Evaluations.
Are Prompt Security and Promptfoo in the same category?
They share AI firewalls and guardrails and AI model and agent security. Prompt Security's primary category is AI firewalls and guardrails and Promptfoo's is AI model and agent security.
Where are Prompt Security and Promptfoo headquartered?
Promptfoo is headquartered in San Francisco, United States.
When were Prompt Security and Promptfoo founded?
Prompt Security was founded in 2023. Promptfoo was founded in 2024.
Who owns Prompt Security and Promptfoo?
Prompt Security is owned by SentinelOne, since 2025. Promptfoo is owned by OpenAI.
What have Prompt Security and Promptfoo announced recently?
March 9, 2026: OpenAI agreed to buy Promptfoo, a startup helping businesses find and fix security issues in AI models during development.

About Prompt Security

Prompt Security offers protection for both employee use of AI tools and the apps an organization builds. Prompt Security continuously tracks prompts per day in organizations of 500 to 1,000 employees.[4][5]

Prompt Security holds that securing agentic AI is fundamentally different from securing traditional software. Prompt Security states that agents act autonomously, call tools and reason over untrusted input, so prompt injection, identity and runtime behavior have to be governed in real time and not only at the perimeter.

Prompt Security provides a security skill suite for OpenClaw, NanoClaw and Hermes agents.[6]

Prompt Security provides a tool that tracks and analyzes OpenClaw deployments across an organization. Prompt Security provides a tool that tests and hardens a system prompt against dynamic LLM-based attacks.[4][9]

Prompt Security publishes news, research, tools and analysis for security teams responding to AI threats. Prompt Security describes an AI gateway as a centralized layer between an organization's users or applications and the AI models or services they call. An AI gateway, as Prompt Security describes it, lets security teams monitor, control and secure that traffic from one place instead of instrumenting every application separately.[4]

Prompt Security curates an interactive, continuously updated directory of 471 companies building security for agentic AI, organized across 14 functional categories. Both pure-play startups and dedicated AI-security lines from larger vendors are in scope for the Prompt Security directory. Entries in the Prompt Security directory are compiled from vendor websites, product documentation, funding announcements, public company registries and analyst coverage. Placement in the Prompt Security directory reflects publicly stated capabilities, not vendor marketing tiers. Category definitions and threat coverage in the Prompt Security directory are mapped against established, independent frameworks for AI and LLM security. The full dataset behind the Prompt Security directory is open and machine-readable.[2][4][5][6][9]

Prompt Security on the record

Sources

Prompt Security full record

  1. [1]Prompt security partners with f5 to secure genai applications with a firewall for ai 302131373Prompt Security via PR Newswire · prnewswire.com · published April 30, 2024 · Tier A
  2. [2]Securing ai promptSentinelOne · sentinelone.com · undated page, accessed September 27, 2026 · Tier A
  3. [3]Sentinelone completes acquisition of prompt securitySentinelOne via The Globe and Mail · theglobeandmail.com · published September 5, 2025 · Tier A
  4. [4]Prompt Security | From SentinelOnePrompt Security · undated page, accessed October 27, 2026 · Tier A
  5. [5]AI Security | AI Glossary | Prompt SecurityPrompt Security · undated page, accessed October 27, 2026 · Tier A
  6. [6]ClawSec: A Security Skill Suite for OpenClaw AgentsPrompt Security · undated page, accessed October 27, 2026 · Tier A
  7. [7]AI Security Startups Map — Agentic AI Vendors by CategoryPrompt Security · undated page, accessed October 27, 2026 · Tier A
  8. [8]About this Map & Methodology — AI Security Startups MapPrompt Security · undated page, accessed October 27, 2026 · Tier A
  9. [9]OneClaw DashboardPrompt Security · undated page, accessed November 10, 2026 · Tier A
  10. [10]Prompt Security Pros and Cons | User Likes & DislikesG2 · undated page, accessed November 10, 2026 · Tier C

Promptfoo full record

  1. [1]PressPromptfoo · promptfoo.dev · undated page, accessed November 4, 2026 · Tier A
  2. [2]promptfoo.devPromptfoo · promptfoo.dev · undated page, accessed November 4, 2026 · Tier A
  3. [3]About Promptfoo | AI Security Experts | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  4. [4]Build Secure AI Applications | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  5. [5]Pricing | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  6. [6]Setting up Promptfoo with CircleCI | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  7. [7]Testing prompts with Jest and Vitest | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  8. [8]Finding LLM Jailbreaks with Burp Suite | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  9. [9]SharePoint Integration | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  10. [10]Langfuse integration | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  11. [11]AI Security for Real Estate | PromptfooPromptfoo · undated page, accessed November 10, 2026 · Tier A
  12. [12]OpenAI acquires Promptfoo to secure its AI agents | TechCrunchTechCrunch · published March 9, 2026 · Tier B
  13. [13]OpenAI Buying AI Security Startup Promptfoo to Safeguard AI Agents - BloombergBloomberg · published March 9, 2026 · Tier B

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