Code · Vendor site 2026-10-04
Phoenix is Arize’s open-source platform for LLM and agent observability, tracing, and evaluation. Teams can run Phoenix locally or self-host in their environment, while optional Arize AX Cloud offers a hosted path to start free without a credit card.
AI engineers and agent builders who need trace collection, eval workflows, and observability in their own environment or via Arize cloud.
Published USD seat pricing on arize.com/pricing applies to Arize AX plans, not a separate monthly list price for the OSS Phoenix server itself.
Phoenix combines tracing and evaluation for LLM agents with a self-host path and optional Arize AX Cloud entry that starts free without a card.
What it can do
Unknown is different from unavailable. Each fact carries its own evidence.
| Capability | Value | Evidence | Checked |
|---|---|---|---|
| Open source | Page describes Phoenix as open-source AI observability and evaluation you can self-host. | Facts sourced | 2026-10-04 |
| Local serve | Homepage shows starting Phoenix locally with uvx arize-phoenix serve. | Facts sourced | 2026-10-04 |
| Tracing and evals | Product copy emphasizes tracing, evaluating, and improving AI agents. | Facts sourced | 2026-10-04 |
Understand the total cost
Free
Free
Open-source Phoenix can be run locally with uvx; AX Cloud offers a free start with no credit card required per the Phoenix page.
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Phoenix is Arize’s open-source platform for LLM and agent observability, tracing, and evaluation. Teams can run Phoenix locally or self-host in their environment, while optional Arize AX Cloud offers a hosted path to start free without a credit card.
Open-source Phoenix can be run locally with uvx; AX Cloud offers a free start with no credit card required per the Phoenix page.. This record lists ongoing free access; check the plan limits before starting.
No paid monthly price is listed; this record treats the product as free to start. See the plan cards for entitlements, billing commitments and seat minimums.
Documentation and SDK integrations for tracing and evaluation are linked from the Phoenix product page and docs.. API access and subscription access may have different terms; consult the linked sources.
Published USD seat pricing on arize.com/pricing applies to Arize AX plans, not a separate monthly list price for the OSS Phoenix server itself.
No retained pricing changes yet. A current price alone does not establish a historical trend.
Reviewed vendor source
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