# Arize Phoenix vs Google Stax

Arize Phoenix is free, with no paid plan attached. Google Stax is free, with no paid plan attached.

| | Arize Phoenix | Google Stax |
|---|---|---|
| Pricing | Free | Free |
| Free to start | Yes | Yes |
| Category | AI Models & Local Execution | AI Models & Local Execution |
| Type | LLM Eval & Observability | LLM Eval & Observability |
| Best for | Fully open-source, self-hostable with zero setup via `uvx` (pip/conda also supported) | Build evals with human raters or LLM autoraters on your own data |

## FAQ

### Arize Phoenix vs Google Stax: what is the difference?

Arize Phoenix is free, with no paid plan attached and is listed for fully open-source, self-hostable with zero setup via `uvx` (pip/conda also supported). Google Stax is free, with no paid plan attached and is listed for build evals with human raters or LLM autoraters on your own data. Both sit in LLM Eval & Observability.

### Is Arize Phoenix or Google Stax cheaper to start with?

Neither — Arize Phoenix and Google Stax are both free, so the choice comes down to capability rather than cost. Both entries list what they uniquely do above.

### Which should I choose, Arize Phoenix or Google Stax?

Choose Arize Phoenix if you need fully open-source, self-hostable with zero setup via `uvx` (pip/conda also supported); choose Google Stax if you need build evals with human raters or LLM autoraters on your own data. Flocci AI Tools does not rank one above the other — it shows both feature sets side by side and lets the requirement decide.

## Related

- [Arize Phoenix](https://aitools.flocci.in/tool/arize-phoenix)
- [Google Stax](https://aitools.flocci.in/tool/google-stax)
- [Arize Phoenix alternatives](https://aitools.flocci.in/alternatives/arize-phoenix)
- [Google Stax alternatives](https://aitools.flocci.in/alternatives/google-stax)
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Source: Flocci AI Tools — https://aitools.flocci.in/compare/arize-phoenix-vs-google-stax

Facts last verified: October 2026