Arize Phoenix is free, with no paid plan attached. Laminar is free, with no paid plan attached. Both are listed under LLM Eval & Observability, so this is a like-for-like comparison. Neither is ranked above the other — Flocci carries no sponsored placement.
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). Laminar is free, with no paid plan attached and is listed for open-source observability and evals platform for AI agents (Apache-2.0). Both sit in LLM Eval & Observability.
Neither — Arize Phoenix and Laminar are both free, so the choice comes down to capability rather than cost. Both entries list what they uniquely do above.
Choose Arize Phoenix if you need fully open-source, self-hostable with zero setup via `uvx` (pip/conda also supported); choose Laminar if you need open-source observability and evals platform for AI agents (Apache-2.0). Flocci AI Tools does not rank one above the other — it shows both feature sets side by side and lets the requirement decide.
| Arize Phoenix | Laminar | |
|---|---|---|
| Pricing tier | Free | Free |
| Free to start | Yes | Yes |
| Category | AI Models & Local Execution | AI Models & Local Execution |
| Type | LLM Eval & Observability | LLM Eval & Observability |
| Listed capabilities |
|
|
| Tags | arize phoenix, llm observability open source, tracing, evaluation, rag debugging, free | laminar lmnr, agent observability, open source agent tracing, browser agent tracing |
| Website | phoenix.arize.com | github.com |
| Full page | Arize Phoenix details → | Laminar details → |
| Alternatives | Arize Phoenix alternatives → | Laminar alternatives → |