Simple, honest pricing
Start free. No credit card required. Scale when your prompt test suite grows. All plans include every assertion type — we don't gate features.
For solo developers and side projects testing prompt quality.
- ✓1,000 assertions / month
- ✓1 project
- ✓All assertion types
- ✓CLI + Python SDK
- ✓Snapshot testing
- ✓Community support (GitHub)
- ✗Slack / webhook alerts
- ✗Unlimited projects
- ✗Team dashboard
- ✗SSO / SAML
- ✗SLA support
For engineers shipping AI features who need real CI-scale coverage.
- ✓50,000 assertions / month
- ✓Unlimited projects
- ✓All assertion types
- ✓CLI + Python SDK
- ✓Snapshot testing
- ✓Priority email support
- ✓Slack & webhook alerts
- ✓Model comparison reports
- ✗Team dashboard
- ✗SSO / SAML
- ✗SLA support
For teams running LLMs in production who need full coverage and SLAs.
- ✓Unlimited assertions
- ✓Unlimited projects
- ✓All assertion types
- ✓CLI + Python SDK
- ✓Snapshot testing
- ✓SLA support (4h response)
- ✓Slack & webhook alerts
- ✓Model comparison reports
- ✓Team dashboard
- ✓SSO / SAML
- ✓Audit logs
Full comparison
Frequently asked questions
What counts as an assertion?
Each call to a pa.assert_* method counts as one assertion. A single test function may run multiple assertions. Assertions are counted per calendar month and reset on the 1st.
Can I switch plans at any time?
Yes. Upgrade or downgrade whenever you need. Upgrades take effect immediately. Downgrades take effect at the next billing cycle.
Which LLM providers are supported?
PromptAssert works with any provider that has a Python SDK: OpenAI, Anthropic, Google Gemini, Cohere, Mistral, and any OpenAI-compatible endpoint.
Do I pay per API call to the LLM?
No. PromptAssert charges for assertion evaluations — the checks we run on your model's output. You pay your LLM provider separately for inference.
Is there a free trial for Pro?
The Free tier is generous enough to evaluate PromptAssert on real tests. If you need a Pro trial for a team eval, email us.
Do you offer discounts for open source projects?
Yes. Open source projects with a public repo get Pro free. Email us with a link to your repo.
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