Stax is Google's AI evaluation platform with managed evaluators and datasets, but it's only available in a handful of countries. PromptLens works worldwide — no Google account needed, transparent pricing, and shareable reports from day one.
A side-by-side look at PromptLens and Stax.
| Feature | PromptLens | Stax |
|---|---|---|
| Available worldwide | Limited regions | |
| No Google account needed | ||
| Shareable report links | ||
| Transparent pricing | From $0 | Not listed |
| Web-based UI | ||
| Multi-model comparison | ||
| Custom evaluators | ||
| Dataset management | ||
| Pre-built evaluators | ||
| Pass/fail scoring | ||
| Latency & token tracking | ||
| LLM-generated datasets | ||
| Image input support | Coming soon |
Available worldwide
No Google account needed
Shareable report links
Transparent pricing
Web-based UI
Multi-model comparison
Custom evaluators
Dataset management
Pre-built evaluators
Pass/fail scoring
Latency & token tracking
LLM-generated datasets
Image input support
How quickly can your team start running evaluations?
Sign up with any email, paste your prompt, add test cases, and run. No Google account needed, no vendor lock-in. Your first evaluation runs in under 5 minutes.
Sign in with a Google account and access the Stax web platform. Import or generate datasets, configure evaluators, and run experiments through the dashboard.
How do non-technical team members participate in prompt QA?
Generate shareable report links for PRs, Slack, or stakeholder reviews. Anyone can view results without an account or technical setup.
Team members need a Google account to access the Stax platform. Collaboration happens within the Stax dashboard — no public sharing links for external stakeholders.
What does it cost and how tied are you to the platform?
Free tier with 3 projects and 50 evaluations/month. Pro at $99/month. Works with 25+ models via OpenRouter — available worldwide, completely vendor-independent.
Stax does not publicly list pricing and is only available in a handful of countries. The platform is tied to Google's ecosystem and requires Google sign-in.
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