How we make this list: we compare pricing pages, product documentation and public user reviews. Ratings come from G2, Capterra or Trustpilot, with the date we checked them.
Promptfoo is the best AI red teaming tool for most teams because its free open source core covers jailbreaks, prompt injection and OWASP LLM risks, and it runs in CI/CD with little setup. Giskard is the strongest alternative for teams that want Python based testing with compliance mapping and continuous red teaming through its paid Hub.
Key takeaways
- Promptfoo, Giskard and Microsoft PyRIT are free at the core, so a small team can start red teaming without a sales call or a licence fee.
- Most enterprise platforms in this list are quote only, so budget planning needs a vendor conversation before a purchase decision.
- Lakera, Mindgard, HiddenLayer and Calypso AI suit regulated or large teams that need scheduled scans, audit ready reports and runtime protection.
- Cisco AI Defense, formerly Robust Intelligence, is the pick for large Cisco shops that want red teaming joined to an AI firewall.
- No single scan proves a model is safe, so pair automated red teaming with human review and retesting after every model or prompt change.
How we picked
We ranked these tools by attack coverage, automation and reporting quality. Attack coverage means jailbreaks, prompt injection, data leakage, bias, harmful content and multi-turn agent attacks. Automation means scheduled scans, CI/CD integration and repeatable campaigns. Reporting means severity scores, framework mapping to OWASP LLM Top 10, NIST AI RMF and MITRE ATLAS, and evidence a security team can act on. Prices are third-party reported and checked 14 Nov 2026. Most enterprise tools are quote only. Where sources disagreed on a price, we flagged the conflict in the tool entry.
Comparison table
| Tool | Best for | Starting price | Free plan |
| Promptfoo | Engineering teams that want red teaming in CI/CD | Free open source core, checked 14 Nov 2026 | Yes, Community tier free |
| Giskard | Python teams testing LLM agents with compliance reports | Free open source library, checked 14 Nov 2026 | Yes, open source library free |
| Lakera | Enterprises that want red teaming plus runtime guardrails | Quote, checked 14 Nov 2026 | Yes, Community plan free |
| Microsoft PyRIT | Security researchers running custom multi-turn campaigns | Free open source, checked 14 Nov 2026 | Yes, MIT licensed |
| Cisco AI Defense | Large Cisco enterprises securing the full AI lifecycle | Quote, checked 14 Nov 2026 | No |
| HiddenLayer | Enterprises that want model scanning, attack simulation and runtime defence together | Quote, checked 14 Nov 2026 | No |
| Mindgard | Regulated teams that need continuous testing with compliance mapping | Quote, checked 14 Nov 2026 | Yes, open source CLI |
| Calypso AI | Enterprises that need automated red teaming behind a firewall | Quote, checked 14 Nov 2026 | No |
Start with Promptfoo if you ship LLM features often and want fast feedback in your build pipeline. It is free and its red team mode covers the OWASP LLM Top 10 with more than 50 attack plugins. Add Giskard or PyRIT when you need deeper Python control or multi-turn attacks such as Crescendo. Move to a paid platform only when you need scheduled scans, SSO, audit logs or a report an auditor will accept.
Open source tools cost nothing for the software itself, but you still pay for the model API calls used to generate and judge attacks. Promptfoo Community is free with a reported cap of 10,000 red team probes per month, and Giskard and PyRIT are free under open source licences. Lakera offers a free Community plan with 10,000 requests per month, while its red teaming service is quoted. The other enterprise tools publish no list price, so expect a sales conversation and a quote based on models tested and scan volume. Price conflict note: some third-party pages still list a Promptfoo Team tier at 50 dollars per month, while November 2026 checks of the vendor pricing page show Community free and Enterprise and On-Premise as quote only, with no 50 dollar tier listed.
What attack coverage should you look for
Good coverage starts with prompt injection and jailbreaks, then adds data leakage, PII exposure, harmful content, bias tests, and tool misuse for agents. Multi-turn attacks matter because a single prompt rarely breaks a guarded model, while a patient conversation often does. Check whether the tool maps findings to OWASP LLM Top 10, NIST AI RMF or MITRE ATLAS, and whether it retests after a fix. If your product is an agent with tools, pick a tool that tests tool calls, not just chat replies.
| Team size and model type | Best choice | Why it fits | Second option |
| Solo developer or small team, single chat model | Promptfoo | Free, fast setup, CI/CD ready, strong plugin library | Giskard |
| Small team, Python LLM agent with tools | Giskard | Python native, agent scenarios, free library to start | Microsoft PyRIT |
| Security research team, custom or novel attacks | Microsoft PyRIT | Scriptable framework, multi-turn strategies, multimodal targets | Promptfoo |
| Mid-size team, customer facing chatbot, needs guardrails too | Lakera | Red teaming plus runtime guardrails, free Community tier | Mindgard |
| Large enterprise, many models, regulated industry | Mindgard | Continuous testing, compliance mapping, remediation guidance | HiddenLayer |
| Large enterprise, Cisco network and security stack | Cisco AI Defense | Red teaming, supply chain scanning and runtime firewall in one platform | HiddenLayer |
| Large enterprise, model files and supply chain risk | HiddenLayer | Model scanning, attack simulation and runtime defence together | Cisco AI Defense |
| Enterprise, air-gapped or on-premise LLM deployment | Calypso AI | Automated red teaming and runtime monitoring behind the firewall | HiddenLayer |
Quick comparison
| Tool | Best for | Starting price | Free plan |
|---|
 Promptfoo | Engineering teams that want free, CI/CD friendly red teaming for LLM apps | Free open source core, checked 14 Nov 2026, Enterprise and On-Premise quote only | Yes, Community tier free with a reported 10,000 red team probes per month |
 Giskard | Python teams that test LLM agents and need compliance mapped reports | Free open source library, checked 14 Nov 2026, Hub and Professional quote only | Yes, open source library free under Apache 2.0 |
 Lakera | Enterprises that want red teaming plus runtime guardrails from one vendor | Quote, checked 14 Nov 2026, Community plan free | Yes, Community plan with 10,000 requests per month |
 Microsoft PyRIT | Security researchers and red teams that build custom multi-turn attack campaigns | Free open source, checked 14 Nov 2026 | Yes, MIT licensed, free to use |
 Cisco AI Defense | Large Cisco enterprises that want red teaming joined to runtime protection and supply chain scanning | Quote, checked 14 Nov 2026 | No |
 HiddenLayer | Enterprises that want model scanning, attack simulation and runtime defence in one platform | Quote, checked 14 Nov 2026 | No |
 Mindgard | Regulated teams that need continuous automated red teaming with compliance mapped reports | Quote, checked 14 Nov 2026 | Yes, open source CLI available for testing individual models |
 Calypso AI | Enterprises that need automated red teaming and runtime monitoring behind their own firewall | Quote, checked 14 Nov 2026 | No |
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#1
Promptfoo
Best for: Engineering teams that want free, CI/CD friendly red teaming for LLM apps
Visit promptfoo.dev
Starting priceFree open source core, checked 14 Nov 2026, Enterprise and On-Premise quote only
Free planYes, Community tier free with a reported 10,000 red team probes per month
Promptfoo started as an LLM evaluation CLI and added red teaming as a first class feature. You declare providers, prompts and test cases in YAML, run the CLI, and get a matrix of results by prompt, provider and test. Its red team mode generates adversarial prompts across OWASP style categories, including prompt injection, jailbreaks, harmful content and PII leakage. OpenAI acquired Promptfoo in March 2026, and both sides said it would stay open source under its MIT licence.
What we like- Free MIT licensed core, more than 50 red team attack plugins, YAML config that fits CI/CD, supports more than 60 providers, clear severity grouped reports
Watch out for- Free red team probes are capped at a reported 10,000 per month, and team dashboards, continuous monitoring and SSO sit in the quoted Enterprise tier
#2
Giskard
Best for: Python teams that test LLM agents and need compliance mapped reports
Visit giskard.ai
Starting priceFree open source library, checked 14 Nov 2026, Hub and Professional quote only
Free planYes, open source library free under Apache 2.0
Giskard is an open source Python library for testing LLM applications and agents, with a paid Hub platform on top. Its scan covers prompt injection, harmful content, stereotypes and misinformation, and it ships a dataset of injection payloads. Version 3, stable in August 2026, generates adversarial suites from a description of your agent. The Hub adds continuous red teaming, role based access and audit logs.
What we like- Python native with pytest style tests, generates attack suites from a plain language description of your agent, maps findings to OWASP LLM Top 10 and EU AI Act, black box testing through an API
Watch out for- The free library is positioned for solo experiments and uses a smaller probe set, while the 50 plus probes, continuous red teaming and SSO in Hub require a quoted contract
#3
Lakera
Best for: Enterprises that want red teaming plus runtime guardrails from one vendor
Visit lakera.ai
Starting priceQuote, checked 14 Nov 2026, Community plan free
Free planYes, Community plan with 10,000 requests per month
Lakera, now part of Check Point AI Security after its 2025 acquisition, sells a platform that covers discovery, risk assessment, runtime protection and adversarial testing. Its AI Red Teaming workflow simulates misuse against models, applications and agents, and an expert led service is sold alongside it. The Guard API screens inputs and outputs through one call, flagging prompt injection, jailbreak attempts, sensitive data leakage and policy violations. Price conflict note: third-party checks report a Community plan at zero dollars per month with 10,000 requests, while Check Point AWS Marketplace listings show AI Red Teaming at 52,000 dollars a year for 1,000 scans. Those are annual bundle list prices, not the vendor site price, so confirm scope with sales.
What we like- Red teaming mapped to OWASP risks, runtime guardrails for prompt injection and data leakage, threat intelligence from the Gandalf game with more than a million players, EU data residency on the Community plan
Watch out for- No public price list on the vendor site, and the pricing page redirects to the console, so enterprise buyers must go through sales
#4
Microsoft PyRIT
Best for: Security researchers and red teams that build custom multi-turn attack campaigns
Visit github.com
Starting priceFree open source, checked 14 Nov 2026
Free planYes, MIT licensed, free to use
PyRIT, the Python Risk Identification Tool, is Microsoft open source framework for red teaming generative AI systems. It was built by Microsoft AI Red Team, open sourced in early 2024, and has since been used to red team hundreds of generative AI products and services. You assemble targets, converters, scorers and attack strategies, and PyRIT keeps every conversation in a memory store you can query later. Pick PyRIT when you need deep control and novel attacks, not a fixed checklist.
What we like- Composable targets, converters, scorers and attack strategies, multi-turn attacks including Crescendo and Tree of Attacks with Pruning, multimodal support for text, image, audio and video, integrated into Azure AI Foundry
Watch out for- It is a framework you script against, not a point and click scanner, so it needs Python skill and setup time, and there is no hosted dashboard included
#5
Cisco AI Defense
Best for: Large Cisco enterprises that want red teaming joined to runtime protection and supply chain scanning
Visit cisco.com
Starting priceQuote, checked 14 Nov 2026
Free planNo
Cisco AI Defense is the current home of Robust Intelligence technology. Cisco acquired Robust Intelligence in October 2024, and its algorithmic red teaming and AI firewall became foundational to Cisco AI Defense. The platform covers discovery of AI assets, detection through supply chain scanning and algorithmic red teaming, and protection with runtime guardrails. Its red team testing simulates interactions with models, agents and AI applications, then generates model specific guardrails. It also scans MCP servers for compromised assets and watches for agent threats such as memory poisoning and tool misuse.
What we like- Algorithmic red teaming across more than 200 threat subcategories, AI supply chain scanning for models and MCP servers, runtime guardrails updated with Cisco Talos threat intelligence, mapping to MITRE ATLAS, OWASP LLM Top 10 and NIST AI RMF
Watch out for- Enterprise only with no free tier or public price, and it fits best inside a Cisco security estate, so smaller teams will find it heavy to adopt
#6
HiddenLayer
Best for: Enterprises that want model scanning, attack simulation and runtime defence in one platform
Visit hiddenlayer.com
Starting priceQuote, checked 14 Nov 2026
Free planNo
HiddenLayer is an Austin based AI security company founded in 2022. Its AI Security Platform runs discovery, supply chain security, attack simulation and runtime security on one platform. Attack Simulation runs continuous adversarial testing aligned to MITRE ATLAS, covering jailbreaks, prompt injection, system prompt extraction and policy bypass. Supply chain scanning checks model artifacts for malware and backdoors, and produces an AI bill of materials.
What we like- Four modules on one platform covering discovery, supply chain security, attack simulation and runtime security, model agnostic with no access needed to weights or training data, works in SaaS, on-premise and air-gapped deployments, independent vendor after a 100 million dollar Series B in September 2026
Watch out for- No public pricing and no free tier, and the homepage gives little technical detail on attack coverage, so buyers must request documentation and a demo
#7
Mindgard
Best for: Regulated teams that need continuous automated red teaming with compliance mapped reports
Visit mindgard.ai
Starting priceQuote, checked 14 Nov 2026
Free planYes, open source CLI available for testing individual models
Mindgard is a Lancaster University spin out, founded in 2022, that builds an automated AI red teaming platform. It profiles an AI system the way an attacker would, mapping models, agents, tools and behaviours before it runs adaptive multi-turn attacks. Findings come with reproducible evidence and remediation guidance, and tests rerun in CI/CD on every change. Its research team has disclosed more than 150 vulnerabilities in production AI products.
What we like- Continuous scheduled testing across LLMs, agents and multimodal models, attacker style reconnaissance that finds exploitable attack paths, remediation guidance for each finding, reports mapped to OWASP, NIST AI RMF, MITRE ATLAS and EU AI Act
Watch out for- No published pricing at any tier, and the pricing page routes to a demo request, so every evaluation starts with a sales conversation
#8
Calypso AI
Best for: Enterprises that need automated red teaming and runtime monitoring behind their own firewall
Visit calypsoai.com
Starting priceQuote, checked 14 Nov 2026
Free planNo
Calypso AI is an enterprise AI security platform built to test, validate and monitor machine learning models and LLM applications. Its automated red teaming simulates adversarial attacks, jailbreaks and prompt injections before deployment, and its runtime monitoring watches for anomalous behaviour in production. F5 acquired Calypso AI in September 2025, and the product is now sold as F5 AI Red Team alongside F5 AI Guardrails.
What we like- Automated red teaming with a large and growing attack library, continuous validation and runtime threat monitoring, on-premise and air-gapped deployment, now backed by F5 after its 2025 acquisition
Watch out for- No public pricing, and enterprise only licensing puts it out of reach for smaller teams, while the rebrand to F5 AI Red Team can confuse buyers
Frequently asked questions
How often should you red team an AI system
Red team before every major release and again after any model change, system prompt change, tool addition or guardrail update, because each change can open a new attack path. For live products, run scheduled scans at least monthly, and weekly for customer facing chatbots or agents with tool access. Open source tools such as Promptfoo and PyRIT can run the same tests in CI/CD on every pull request.
Can free open source tools replace a paid red teaming platform
Free tools can replace a paid platform for attack generation and basic reporting, but they do not replace managed scheduling, team workflows, SSO, audit logs or auditor ready reports. Promptfoo, Giskard and PyRIT cover the core testing well. Pay for a platform when compliance or scale matters, or when your team lacks the time to maintain test pipelines.
What is the difference between red teaming and guardrails
Red teaming is offensive testing before release, where you attack the model on purpose to find weaknesses. Guardrails are defensive controls at runtime, where you screen inputs and outputs and block unsafe content in production. You need both, because red teaming finds the gaps and guardrails reduce the harm when a new attack slips through. Lakera, Cisco AI Defense, HiddenLayer and Calypso AI sell both layers.
Do AI red teaming tools test agents as well as chat models
Some do, and some do not, so check before you buy. PyRIT, Giskard Hub, Mindgard and Cisco AI Defense test agent behaviour, including tool calls, multi-turn planning and MCP connected tools. If your agent can send email, run code or move money, pick a tool that tests tool misuse, privilege escalation and memory poisoning, not just single turn chat replies.
How do you act on a red teaming report
Start with the highest severity findings that are reproducible, fix the model prompt, guardrail or tool permission behind each one, then rerun the same attack set to confirm the fix. Record the evidence, the fix and the retest result for audit. Do not treat a clean scan as proof of safety, because attackers keep finding new prompts.
Sources we checked (18)
- https://www.aievals.co/tools/promptfoo
- https://awesomeagents.ai/tools/best-ai-red-teaming-tools-2026/
- https://www.aievals.co/tools/giskard
- https://startupstash.com/best-ai-red-teaming-tools/
- https://aicompliancevendors.com/vendors/lakera
- https://www.anygen.io/showcase/lakera-ai/index.html
- https://commandline.microsoft.com/pyrit-python-risk-identification-tool-ai-red-teaming-subject-matter-experts/
- https://vdf.ai/blog/ai-red-teaming-tools/
- https://www.cisco.com/site/us/en/products/security/ai-defense/robust-intelligence-is-part-of-cisco/index.html
- https://www.cisco.com/c/en/us/products/collateral/security/ai-defense/ai-defense-so.html
- https://aicompliancevendors.com/vendors/hiddenlayer
- https://aws.amazon.com/marketplace/pp/prodview-2haypjrayfxgw
- https://mindgard.ai/automated-ai-red-teaming
- https://www.toolglade.com/tool/mindgard
- https://agentbeam.com/blog/ai-agent-security-market-2026
- https://ones.com/blog/tool-guide/top-tools-for-ai-risk-23/
- https://www.f5.com/company/blog/agentic-signature-attack-packs
- https://www.confident-ai.com/knowledge-base/compare/best-ai-red-teaming-tools-2026
Is your product missing or out of date?
We review this list regularly. Vendors can request a listing, send updated pricing or ask about featured placement.
Shihab Mia · Founder, Rankite
Shihab has 5+ years in B2B and SaaS SEO. He writes Rankite's software buying guides from pricing pages, documentation and public user reviews. More about Shihab.