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best 10 ai red-teaming tools

ranked on what you can actually run today — because a third of this category has been acquired, and the three best options are free.

last reviewed 29 jul 2026 · 10 tools tested ·list curated by Onur Ozcanxin

the short version
best overallPromptfooany team that wants to start testing this week without a procurement conversation.88/100runner-upGarakscanning a specific model for known failure modes, with something citable to show for it.85/100

we looked at sixteen names and four of them no longer exist as things you can buy. cisco acquired robust intelligence in august 2024 and it now ships only inside cisco ai defense. f5 absorbed calypsoai so completely that calypsoai.com redirects to an f5 product page carrying no trace of the name. palo alto did the same to protect ai, whose domain now forwards into prisma airs. and cato networks acquired aim security in october 2025, with aim.security reduced to a bare redirect. anyone comparing this category from a list written a year ago is comparing four dead brands.

a fifth has quietly left. patronus ai's own homepage now leads with simulation research and 'digital world models' aimed at agi, with red-teaming demoted to a legacy capability and no dedicated product page we could find. a sixth, haize labs, blocks automated access to every page it has, so nothing about it could be verified firsthand and it isn't ranked.

of what remains, the commercial vendors publish essentially nothing. no per-test rate, no seat price, no tier — every one of them routes you to a demo booking. lakera and repello offer a free entry point and neither publishes what the paid product costs. after eight vendors that pattern stops being a coincidence and becomes the category's defining characteristic.

which is why the top of this ranking is open source. promptfoo is mit with a free tier covering 10,000 probes a month and tests applications and agent tool access, garak is apache 2.0 from nvidia with a peer-reviewed paper behind it, and microsoft's pyrit is mit. you can read their licences, run them today, and see exactly what they test — none of which is true of anything sold here.

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  1. 1

    Promptfoo

    mit-licensed, free for ten thousand probes a month, and the only free tool here that tests agent tool access.

    88/100

    verdictthe most capable thing here you can run today, and the only free option that understands your application rather than just your model.

    best for
    any team that wants to start testing this week without a procurement conversation.
    price
    free
    pricing note
    community tier free with red-teaming capped at 10,000 probes a month; enterprise and on-premise are both quote-only with no published figure
    free tier
    yes
    pricing
    free tier; enterprise quote-only
    self-serve
    yes
    tests
    model, application and agent tools
    licence
    mit
    compliance mapping
    claimed, not itemised

    mit-licensed with a genuinely usable free allowance — 10,000 red-team probes a month — covering more than 50 named vulnerability types: prompt injection, jailbreaking, rag document exfiltration, system-prompt override, malicious resource fetching, pii leakage, unauthorised data access and tool and function discovery.

    that last one matters. promptfoo frames its testing as 'dynamic attacks tailored to your application' including agent tool discovery, which puts it at the application and agent layer rather than probing a bare model. garak, its closest free rival, tests a single model and cannot tell you anything about what an agent does with its tools.

    two honest limits. scaling past the free tier means enterprise or on-premise, both quote-only with no published price — the same wall as every commercial vendor here. and while it claims mapping to owasp, nist and the eu ai act for audit-ready reporting, the specific mapping isn't itemised, so verify it covers what your auditor asks for.

    pros
    • +mit licence with a real 10,000-probe monthly free tier
    • +50+ named vulnerability types including tool discovery
    • +tests the application and agent layer, not just the model
    • +self-serve install with no sales contact
    cons
    • enterprise and on-premise pricing is quote-only
    • compliance mapping claimed but not itemised
    • supporting research hosted separately and unverified
    • free tier cap will bind on any serious programme
  2. 2

    Garak

    apache 2.0 from nvidia, twenty-plus probe modules, and a peer-reviewed paper behind it.

    85/100

    verdictthe most rigorous free option and the narrowest in scope — it tests a model beautifully and knows nothing about the application around it.

    best for
    scanning a specific model for known failure modes, with something citable to show for it.
    price
    free
    pricing note
    apache 2.0, no paid tier at all; install from pypi or github and run it
    free tier
    yes
    pricing
    free
    self-serve
    yes
    tests
    model only
    licence
    apache 2.0
    compliance mapping
    none

    apache 2.0, maintained under nvidia's github organisation with leon derczynski as co-copyright holder, and backed by a peer-reviewed preprint on arxiv that users are asked to cite. in a category where most vendors publish marketing copy, having a paper to point at is a meaningful difference.

    the probe coverage is broad for model-level work: hallucination, data leakage, prompt injection, misinformation, toxicity, jailbreaks including dan-style attacks, encoding-based injection, malware generation, package hallucination and xss-style output, across more than twenty modules. it runs from the command line against a named target model with no account and no sales contact.

    the boundary is firm and worth understanding before you rely on it. garak points at a single llm directly. it does not test the application wrapping that model, and it does not test what an agent does with its tools — so it cannot answer the questions that make agentic deployments risky. no compliance-framework mapping either.

    pros
    • +apache 2.0 with no paid tier or account required
    • +20+ probe modules covering a wide failure taxonomy
    • +peer-reviewed arxiv preprint behind the methodology
    • +actively maintained under nvidia's organisation
    cons
    • model-level only — no application or agent testing
    • cannot assess agentic tool abuse at all
    • no compliance-framework mapping out of the box
    • command-line only, no reporting layer
  3. 3

    Adversa AI

    the most itemised attack taxonomy and the only vendor naming five compliance frameworks — behind a demo form.

    82/100

    verdictthe most concrete commercial vendor here on both what it tests and what it maps to — and you cannot find out what any of it costs.

    best for
    teams securing ai coding agents, where its current flagship is aimed.
    price
    not published
    pricing note
    no pricing, tiers or self-serve checkout anywhere; every path leads to a demo request
    free tier
    no
    pricing
    none published
    self-serve
    no
    tests
    model, agent and application
    licence
    proprietary
    compliance mapping
    five named frameworks

    the attack taxonomy is genuinely itemised rather than gestured at: model-level jailbreaks, adversarial prompts, poisoning and safety bypasses; agentic tool hijack, goal manipulation and inter-agent and tool-chain abuse; and application-level context contamination, auth bypass, data exfiltration and session abuse. after reading gray swan describe 'emerging attacks', that specificity is the differentiator.

    it is also the only vendor here mapping to five named frameworks — owasp asi for agentic security, nist ai rmf, the eu ai act, cosai and mitre — and it publishes named vulnerability research, including a cursor deeplink remote-code-execution finding and a shell-injection issue it calls guardfall, plus a threat-intel feed it says ingests over 3,000 sources monthly.

    two caveats. there is no pricing and no self-serve path at all. and the flagship has narrowed to runtime security for ai coding agents specifically — cursor, claude code, copilot — with general red-teaming positioned as a companion service, so confirm the scope matches what you actually need.

    pros
    • +most itemised attack taxonomy across model, agent and application
    • +maps to owasp asi, nist ai rmf, eu ai act, cosai and mitre
    • +publishes named vulnerability research with real findings
    • +continuous runtime testing rather than point-in-time only
    cons
    • no pricing or self-serve path whatsoever
    • flagship narrowed to ai coding-agent runtime security
    • general red-teaming is now a companion service
    • no free tier to evaluate
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  4. 4

    PyRIT

    microsoft's mit-licensed red-team framework — build your own attacks, and the repository just moved.

    79/100

    verdictthe most flexible free option and the one that gives you least out of the box — it's a toolkit, not a scan.

    best for
    security teams with engineering capacity who want to encode their own threat model.
    price
    free
    pricing note
    mit licence, no paid tier; a framework for assembling red-team orchestration rather than a scanner you point and run
    free tier
    yes
    pricing
    free
    self-serve
    yes
    tests
    whatever you build
    licence
    mit
    compliance mapping
    none

    mit-licensed and maintained by microsoft, pyrit is a framework for building red-team orchestration against generative ai systems, covering prompt injection, jailbreaks and harmful-content generation among its stated risk categories. because it's a toolkit rather than a fixed probe catalogue, what it actually tests depends on what you build with it.

    that is the trade against garak. garak ships twenty-plus probes you can run immediately; pyrit ships the machinery to construct attacks specific to your system and threat model. for a team with the engineering capacity to use it, that's more powerful. for a team wanting a scan this afternoon, it's more work.

    one practical trap: the canonical repository moved from the azure organisation to the microsoft organisation, and the old azure/pyrit location was archived read-only on 27 march 2026. search results and older documentation still point at the archived one, so check which url you're installing from.

    pros
    • +mit licence, maintained by microsoft
    • +fully flexible — encode your own threat model
    • +no account, no sales contact, no cost
    • +built by and for practising red teams
    cons
    • no out-of-box probe catalogue — significant setup effort
    • repository moved; the old azure location is archived
    • no published compliance-framework mapping
    • model-versus-application scoping is left to you
  5. 5

    Lakera

    the only commercial vendor here you can start using without talking to anyone.

    76/100

    verdictgenuinely lower friction than anything else commercial here — with the red-teaming service sold separately from the product you can actually sign up for.

    best for
    smaller teams wanting runtime guardrails in place before commissioning a red-team engagement.
    price
    free tier available
    pricing note
    a free self-serve tier exists; the pricing page loads but displays no figures or tiers for anything above it
    free tier
    yes
    pricing
    free tier; paid unpublished
    self-serve
    yes, for guardrails
    tests
    application layer, runtime
    licence
    proprietary
    compliance mapping
    owasp, via third party

    lakera is the only paid vendor in this ranking with a confirmed free self-serve entry point. that alone distinguishes it in a category where every other commercial option routes you to a demo booking before you learn anything.

    what it tests: direct and indirect prompt injection, ai data leakage, toxic content generation, and multilingual and multimodal attacks, with model-agnostic guardrails that sit in front of whatever you're running. it maintains a 1,000-plus member practitioner community and publishes guides including an agentic ai security playbook.

    two things to be clear about. the self-serve signup gets you the guardrail and firewall product; the 'ai red teaming' line — automated risk-based testing plus expert-led adversarial engagements — is marketed separately and is not what you get by signing up. and the pricing page renders without any numbers on it, so what the paid tiers cost is unknown.

    pros
    • +only commercial vendor here with free self-serve signup
    • +covers direct and indirect prompt injection plus data leakage
    • +model-agnostic runtime guardrails
    • +active practitioner community and published playbooks
    cons
    • pricing page shows no figures for any paid tier
    • red-teaming service is separate from the self-serve product
    • no first-party compliance-framework mapping found
    • red-team methodology and benchmarks not detailed
  6. 6

    HiddenLayer

    fifty disclosed cves and thirty patents, across the broadest claimed scope here.

    73/100

    verdictthe most credible research track record among the commercial vendors, attached to product claims too broad to verify without a sales call.

    best for
    enterprises wanting model supply-chain scanning alongside runtime protection from one vendor.
    price
    not published
    pricing note
    no pricing anywhere; enterprise only, with 'book a demo' throughout
    free tier
    no
    pricing
    none published
    self-serve
    no
    tests
    supply chain, application, runtime
    licence
    proprietary
    compliance mapping
    none found

    50-plus disclosed cves and 30-plus issued patents is a concrete, checkable claim, and stronger evidence of real security work than the 'expert research team' language several competitors rely on. it also publishes an annual ai threat landscape report.

    the platform spans four named pillars — ai discovery to inventory your ai assets, ai supply chain security for model and artifact risk, ai attack simulation, and ai runtime security. model supply-chain scanning is genuinely differentiated: most vendors here test behaviour, not the provenance of the artefacts you're deploying.

    the specifics thin out under inspection. the attack-vector claims are described as covering the ai lifecycle rather than itemised by category, we could not locate a dedicated red-teaming methodology page — two url attempts returned 404 — and no compliance-framework mapping appeared on any page we reached. confirming what the red-teaming product actually does would require the demo.

    pros
    • +50+ disclosed cves and 30+ patents
    • +model supply-chain scanning, rare in this category
    • +spans discovery, supply chain, simulation and runtime
    • +publishes an annual threat landscape report
    cons
    • no pricing published at all
    • red-teaming methodology page returns 404
    • attack coverage described broadly rather than itemised
    • no compliance-framework mapping found
  7. 7

    SPLX

    publishes red-team findings against named frontier models, and open-sourced the agent-mapping half of its product.

    71/100

    verdictthe most useful free artefact of any commercial vendor here, alongside published attacks on models people actually use.

    best for
    teams wanting to map an agent's tool graph for free before deciding whether to buy the platform.
    price
    not published
    pricing note
    core platform is demo-gated with no published figures; the agentic radar component is separately open source on github
    free tier
    yes
    pricing
    none published
    self-serve
    agentic radar only
    tests
    model, application and agent
    licence
    open component, closed platform
    compliance mapping
    generic, unnamed

    splx publishes named red-team research against specific frontier models — gpt-5, claude opus 4.1 and grok 4 — plus an agentic red-teaming whitepaper. testing models people actually deploy, and saying what was found, is more useful than a vendor's own bypass-rate statistics.

    agentic radar, its agent and tool-graph mapping tool, is open source on github and separable from the paid platform. for anyone trying to understand what their agent can reach before buying anything, that's a genuinely free starting point — though we did not fetch its licence file, so confirm the terms before depending on it.

    the rest is the category norm. the core testing and guardrail platform is demo-gated with no published price, and its compliance language refers to 'global and custom security standards' without naming a framework. note also that the company now presents as splx rather than splxai, so the older name is legacy.

    pros
    • +published red-team reports on gpt-5, claude opus 4.1 and grok 4
    • +agentic radar open-sourced for agent and tool mapping
    • +covers model, application and agent layers
    • +agentic red-teaming whitepaper published
    cons
    • core platform pricing entirely undisclosed
    • no named compliance framework
    • agentic radar licence not verified
    • rebranded from splxai — older references are stale
  8. 8

    Mindgard

    a hundred disclosures against systems you've heard of, from a lab with a decade of university research behind it.

    68/100

    verdictthe disclosure record is the argument, and it's a decent one — everything else about the commercial offer is behind a form.

    best for
    buyers who weight demonstrated findings against real systems over published methodology.
    price
    not published
    pricing note
    the pricing page carries no figures or tiers — demo booking only
    free tier
    no
    pricing
    none published
    self-serve
    no
    tests
    model, application and agent
    licence
    proprietary
    compliance mapping
    none — soc 2 only

    mindgard claims more than 100 public vulnerability disclosures against major ai systems, naming google antigravity, openai sora and xai grok among them. specific named targets are more persuasive than an unnamed count, and the company traces its methods to over a decade of ai-security research at lancaster university.

    the product spans attack-surface enumeration, what it calls psychometric agent profiling, automated red-teaming across chatbots, applications and agentic workflows, and runtime protection with automated agent hardening — model, application and agent layers all covered on its own description.

    two things to note. there is no pricing on the pricing page and no self-serve path. and the only compliance badge shown is aicpa soc 2 type ii, which is a general information-security certification rather than a mapping to any ai framework — easy to mistake for one when it appears next to red-teaming claims.

    pros
    • +100+ public disclosures naming real frontier systems
    • +over a decade of university ai-security research heritage
    • +covers model, application and agentic workflows
    • +soc 2 type ii certified
    cons
    • pricing page contains no pricing
    • no self-serve path at all
    • soc 2 is general infosec, not ai-framework mapping
    • no detailed public methodology document found
  9. 9

    Gray Swan AI

    runs a public attack competition that finds real exploits — and describes its actual product in adjectives.

    65/100

    verdicta genuinely novel model for finding novel attacks, wrapped around a commercial offer you cannot evaluate from outside.

    best for
    frontier labs commissioning pre-release adversarial evaluation, and researchers wanting to compete.
    price
    not published
    pricing note
    no pricing anywhere; shade, cygnal and the red-team services are all sales-gated, with only the public arena competition openly accessible
    free tier
    yes
    pricing
    none published
    self-serve
    arena only
    tests
    model and agent, scope vague
    licence
    proprietary
    compliance mapping
    none named

    the arena is the interesting part: a crowdsourced attack competition with open enrolment and cash prizes, feeding discovered exploits back into gray swan's defences. it claims three million attack attempts and says most arena-discovered exploits remain unpublished. as a discovery mechanism for genuinely new jailbreaks that's more likely to work than an internal team, and it names google deepmind, openai, anthropic and meta as customers or partners.

    it also publishes system cards for evaluations of frontier models including claude and gpt, and maintains a research hub it says holds 150-plus curated tools and datasets.

    the commercial product is the opaque part. shade for red-teaming and cygnal for runtime protection are entirely sales-gated, and the testing scope is described in marketing terms — 'emerging attacks', protection tuned to 'your enterprise agent's tools, data and workflows' — rather than itemised attack categories. no named compliance framework appears anywhere, only references to 'emerging ai safety frameworks'.

    pros
    • +crowdsourced arena competition genuinely surfaces novel attacks
    • +publishes system cards for frontier model evaluations
    • +names deepmind, openai, anthropic and meta as partners
    • +arena is openly accessible to researchers
    cons
    • commercial products entirely sales-gated with no pricing
    • testing scope described in marketing language, not categories
    • no named compliance framework
    • most arena findings are unpublished
  10. 10

    Repello AI

    a free scan you can run without a sales call, behind numbers nothing supports.

    60/100

    verdictthe free entry point is real and useful; the headline capability claims have no methodology, paper or benchmark behind them that we could find.

    best for
    a no-commitment first look at how an application responds to adversarial input.
    price
    free scan available
    pricing note
    a free 'recon' scan is offered self-serve; the full platform has no published price and requires a demo
    free tier
    yes
    pricing
    free scan; platform unpublished
    self-serve
    yes, for recon
    tests
    application and agent, black-box
    licence
    proprietary
    compliance mapping
    claimed, not itemised

    the recon scan is a genuine self-serve starting point in a category that mostly refuses to give you one, and the described coverage is relevant: prompt injection, jailbreaks against safety guardrails, data exfiltration through context windows and rag pipelines, excessive agent autonomy, tool abuse and api exploitation, and resource exhaustion. testing is black-box and model-agnostic across openai, gemini, anthropic, llama and hugging face, and claims multimodal and 100-plus language coverage.

    the headline numbers are where it loses ground. 270-plus vulnerability types and 15 million evolving attack patterns are large, specific-sounding figures with no paper, benchmark, disclosure record or methodology behind them that we could locate. against adversa's named cve-style findings and garak's peer-reviewed paper, that's assertion rather than evidence.

    we also could not confirm basic corporate details — attempts to reach an about or company page returned 404 — so its independence is an absence of contrary evidence rather than a verified fact, and the full platform's price is unpublished.

    pros
    • +free self-serve recon scan with no sales call
    • +black-box and model-agnostic across major providers
    • +covers agent autonomy and tool abuse explicitly
    • +claims multimodal and 100+ language coverage
    cons
    • 270+ vulnerability types claim has no supporting evidence
    • 15m attack patterns claim likewise unsupported
    • about and company pages return 404
    • full platform pricing unpublished

how this ranking was made

we checked corporate status before anything else, and it changed the shape of the ranking more than any other field. four acquisitions and one repositioning removed five of sixteen candidates, and rather than replace them quietly we've named them in the intro, because 'this vendor no longer exists independently' is the most useful thing a buyer can learn about them.

for open-source tools we read the licence file: apache 2.0 for garak, mit for pyrit and promptfoo. we also record what a paid tier adds, since promptfoo's free allowance is real but capped and everything above it is quote-only.

we distinguish what a tool tests at three levels — the model alone, the application wrapping it, or the agent's tool access. that distinction decides whether a tool is relevant to you at all: garak is excellent and tests a single model directly, which means it cannot tell you anything about an agent abusing its own tools.

compliance mapping is reported only where a named framework appears. adversa names owasp asi, nist ai rmf, the eu ai act, cosai and mitre; most name nothing, and mindgard's soc 2 badge is a general infosec certification rather than an ai-framework mapping, which is easy to misread as one.

capability claims are attributed and, where they are unsupported, said to be. repello advertises 270+ vulnerability types and 15 million attack patterns with no methodology, paper or benchmark behind them that we could find, and gray swan describes its testing in marketing language rather than itemised attack categories. we report the claim and the absence of evidence together.

our general methodology and disclosures →
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