Arize Phoenix
Free, self-hosted LLM tracing and evaluation
Overview
Phoenix is Arize AI's free, self-hosted platform for tracing, evaluating and iterating on LLM applications and agents: OpenTelemetry-based traces, LLM-as-a-judge evals, datasets, experiments and a prompt playground. It is source-available under the Elastic License 2.0; Arize sells a separate managed platform, Arize AX.
Pricing
Pricing shown for reference only. These figures reflect RECATOOLS research as of 12 Oct 2026 and may be out of date or incomplete. This is not financial or purchasing advice — always confirm the current price on the provider’s official website before making any decision.
Use cases
What you can produce with Arize Phoenix
- Traces of every step of an LLM app or agent run in a span-tree view
- OpenInference and OpenTelemetry instrumentation for major agent frameworks
- LLM-as-a-judge and custom evaluators over traces and datasets
- Versioned datasets and experiments for prompt, model or retrieval changes
- A prompt playground that replays traced calls
- A remote MCP server for querying Phoenix from coding agents
- Self-hosting via pip, Docker or Helm with PostgreSQL
Arize Phoenix is one of the most complete no-cost options for finding out why an agent or RAG pipeline behaved as it did: OpenTelemetry tracing, evals, datasets, experiments and a prompt playground, self-hosted with no feature gates.
Note the licence: Elastic License 2.0 is source-available and bars offering Phoenix as a hosted service, though internal use is unrestricted. Teams wanting a managed service or SLAs would look at Arize AX, which hosts data only in the US, EU or Canada.
What we found
Phoenix is Arize AI's free, self-hosted platform for seeing what an LLM application or agent actually did and whether it did it well. It covers four linked jobs: OpenTelemetry-based tracing of prompts, retrievals and tool calls; evaluations, including LLM-as-a-judge scoring; versioned datasets and experiments; and a prompt playground that can replay traced calls. Newer additions include PXI, an assistant built into the interface for working through traces, and a remote MCP server that lets coding agents such as Claude Code query a Phoenix instance directly. The project ships often: version 20.21.0 was released on 11 October 2026.
The licence needs reading correctly. Arize markets Phoenix as open source, but the code is under the Elastic License 2.0, a source-available licence whose main restriction is that you may not offer Phoenix to others as a hosted service. For a team running it for its own applications that rarely matters, and Arize's self-hosting guide promises no licence fees, usage limits or feature gates. Earlier versions of this page called the licence permissive. Setup is light: a pip or uvx install, a Docker image or a Helm chart, with PostgreSQL for production. Self-hosting Langfuse, by comparison, involves PostgreSQL, Redis, ClickHouse and object storage, according to Langfuse's own documentation.
Arize makes its money from Arize AX, a separate managed platform with a free tier, a $50-a-month Pro plan and custom Enterprise contracts. Phoenix itself carries no SOC 2 or HIPAA attestation because it runs on your infrastructure; compliance follows your environment, and support comes from the community rather than an SLA.
In Asia the signals are partnerships rather than local infrastructure: Tokyo Electron Device resells Arize AX in Japan, and LG Uplus signed a memorandum with Arize in September 2026. AX hosts data only in the US, EU or Canada, so teams in Southeast Asia with residency rules are better served by self-hosted Phoenix, which keeps every trace inside their own network.
Compiled by RECATOOLS from public sources: vendor documentation and pricing, code repositories and published reporting.
About this listing
This entry was compiled from publicly available data including Arize Phoenix's official website, press releases, documentation, and reputable third-party publications. RECATOOLS is not affiliated with Arize Phoenix unless explicitly stated.
Third-party AI tools update their pricing, features, availability, and policies frequently. Information here may be outdated by the time you read this — we make reasonable efforts to keep listings current, but cannot guarantee absolute accuracy.
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