Arize Phoenix vs PromptLayer

In short

• Both: Self-hosted, API, Traces and evaluates
• Only Arize Phoenix states: Command line
• Only PromptLayer states: Official SDKs, Builds agents and workflows

Arize Phoenix

Open-source platform for tracing, evaluating, and improving AI agents and LLM applications.

Plans

AX Free

Free

• 10 issues per month
• 25k spans per month
• 1 GB per month
• 15 days retention
• SaaS deployment
• Unlimited users and evals

AX Pro

• $50 per month

• 25 issues per month
• 50k spans per month
• 10 GB per month
• 30 days retention
• SaaS deployment
• Unlimited users and evals

AX Enterprise

Price on request

• Unlimited issues
• Custom span volume
• Custom ingestion volume
• Custom retention
• SaaS or Self-Hosted deployment
• Unlimited users and evals

Prices checked 2026-09-25 on the maker’s page.

Capabilities

• Command line — “Get Started Locally $ uvx arize-phoenix serve” source
• Self-hosted — “Self-host Phoenix and keep sensitive data on your own infrastructure.” source
• API — “Docs Quickstarts, API reference, and integration guides” source
• Traces and evaluates — “Phoenix shows every step your agent takes so you know what went wrong.” source

Security

• SOC 2 Type II — “Arize AI Announces SOC 2 Type II Certification” source
• SOC 2 — “Arize AI Announces SOC 2 Type II Certification” source
• ISO 27001 — “ISO/IEC 27001 Certified” source
• GDPR — “GDPR Compliant” source
• HIPAA — “HIPAA Compliant” source
• Data kept in the EU — “Arize AI: Support for EU Data Residency” source

Latest updates

• 2026-09-17 Get Alyx help tailored to your experience

  Alyx adapts how it helps based on your experience level in each part of Arize AX.

• 2026-09-17 Pick up where you left off with Alyx long-term memory

  Alyx remembers context across conversations, including preferences, goals, project and asset learnings, team conventions, and decisions.

• 2026-09-08 Add and annotate entire sessions and traces in annotation queues

  Send sessions and traces to an annotation queue and review them at session or trace granularity.

PromptLayer

PromptLayer helps AI teams manage prompts, run evaluations, trace agents, and monitor LLM application usage.

Plans

Free

Free

• 5 users
• 2.5k/month requests
• 1 workspace
• 250/month Eval Cell Executions
• 10MB max per Dataset

Pro

• $49 per month

• Same limits as in Free, plus
• Unlimited Playgrounds
• Unlimited Workspaces
• 150MB max per Dataset

Team

• $500 per month

• 25 Users
• 100k+/month Requests
• 7.5k+/month Eval Cell Executions
• 1GB max per Dataset

Enterprise

Price on request

• Custom limits on everything
• Role Based Access Controls
• Deployment Approvals
• HIPAA with BAA
• Flexible Hosting Options
• Dedicated Support

Prices checked 2026-09-26 on the maker’s page.

Capabilities

• Self-hosted — “Enterprise Self-hosted, managed single-tenant” source
• API — “PromptLayer provides versioned prompts, programmatic APIs, webhooks, and evaluation workflows for controlled CI/CD releases.” source
• Official SDKs — “Treat prompt versions like deployable software artifacts: retrieve them through an SDK or REST API, run regression evaluations when they change, and promote release labels only after checks pass.” source
• Builds agents and workflows — “Build, trace, and improve agent workflows with prompts, tool calls, evaluations, and logs in one place.” source
• Traces and evaluates — “Connect production traces to prompt versions, inspect failures, and track cost, latency, and token usage.” source

Latest updates

• 2026-09-14 Deployment 1

  General performance and stability improvements

• 2026-09-10 Deployment 1

  Structured Search accepts Ctrl+Enter; FOR_LOOP column variable mappings are preserved; multi-value badges handle overflow and text wrapping.

• 2026-09-08 Deployment 1

  Added Gemini 3.8 Flash support across Google AI Studio, Vertex AI, and OpenRouter; updated GPT-5.6 Sol and Sol Pro pricing.