Pay-as-you-go
$10-20
Per 1,000 API calls
- $5 free credits
- Smaller evaluators ($10/1k)
- Larger evaluators ($20/1k)
- Self-service access
- API access
Patronus AI — Observability, Prompts & Evals Platform
Founded 2024|San Francisco, California|11-50 people|Enterprise
What is Patronus AI?
Patronus AI is a San Francisco startup founded by former Meta machine learning experts Anand Kannappan and Rebecca Qian, focused on automatically detecting costly and dangerous LLM mistakes at scale. The company raised USD 17 million in Series A funding led by Notable Capital, bringing total funding to USD 20 million. Patronus AI developed a first-of-its-kind automated evaluation platform that identifies errors like hallucinations, copyright infringement, and safety violations in LLM outputs. The platform uses pay-as-you-go pricing starting at USD 10-20 per 1,000 API calls, with USD 5 in free credits for new users. Trusted by companies like OpenAI, HP, Pearson, AngelList, and Etsy, Patronus AI has processed millions of requests, catching hundreds of thousands of hallucinations. Customers praise the research-first approach and 20% better evaluation performance than competing methods, though as a startup-stage company, many processes are still being built.
Key features
Core capabilities this platform advertises.
- Automated LLM evaluation platform
- Hallucination detection
- RAG-specific evaluation metrics
- Red-teaming capabilities
- CI/CD integration
Strengths and tradeoffs
What this tool does well, and the limitations to keep in mind.
Pros
- 20% better evaluation performance than competitors
- Trusted by OpenAI, HP, Pearson, and major enterprises
- Research-first approach from Meta ML experts
- Pay-as-you-go removes barriers to entry
Cons
- Very early stage with processes still being built
- Startup maturity risks typical of young companies
- Integration breadth still developing
Plans & pricing
What's included in each plan, and how the tiers compare.
Enterprise
Custom
Annual contract
- Higher rate limits
- Custom evaluation models
- Webhooks
- AI Professional Services
- Custom security
- Private deployment
Common use cases
AI teams that need rigorous, automated quality evaluation and safety testing
- Detecting hallucinations in production
- RAG quality evaluation
- Adversarial testing of LLM systems
- Continuous evaluation in CI/CD
- Model comparison and selection
Using Patronus AI with Respan
Integrate Patronus AI's evaluation platform with Respan to automatically detect hallucinations, copyright violations, and safety issues in your LLM outputs. Add comprehensive quality gates to AI workflows with research-backed evaluation. With Respan orchestrating Patronus AI alongside your LLM providers, ensure reliable, safe AI applications.
- Detect hallucinations automatically with 20% better accuracy
- Catch copyright infringement before deployment
- Assess model performance across accuracy, safety, and brand alignment
- Start with USD 5 free credits for immediate testing
Best Patronus AI alternatives & competitors
Top companies in Observability, Prompts & Evals you can use instead of Patronus AI.
Respan
LLM tracing, evals, and gateway
LangSmith
Trace visualization for LLM chains
Weights & Biases
ML experiment tracking
MLflow
OpenTelemetry-native tracing
Langfuse
Open-source LLM observability
Arize AI
ML observability with LLM support
Helicone
Traceloop
OpenTelemetry
Datadog LLM
LLM monitoring within Datadog platform
HoneyHive
Prompt management
Braintrust
Real-time LLM logging and tracing
Phoenix
OpenTelemetry-based LLM and agent tracing
Promptfoo
Humanloop
Portkey
Sentry
DeepEval
Ragas
RAG-specific evaluation framework
LangWatch
Multi-turn agent simulation testing
Galileo AI
LLM output quality evaluation
PromptLayer
Maxim AI
Distributed tracing for LLM and agent apps
Confident AI
DeepEval open-source evaluation framework
Opik
Agenta
Future AGI
Multimodal evaluation (text, image, audio, video)
Lunary
Parea AI
Moda
Hallucination detection
Ashr
Multi-modal synthetic testing
Sentrial
Agent failure root cause analysis
Athina AI
Chamber
ML infrastructure automation
Compare Patronus AI
Side-by-side comparisons with other tools in this category.
Best integrations for Patronus AI
Companies from adjacent layers in the AI stack that work well with Patronus AI.
Last verified: March 10, 2026