Arize Phoenix vs Braintrust
No leader: the top candidate Braintrust has only 0.31 confidence (low), below the 0.35 needed to declare a winner. The attribute-by-attribute breakdown below, with a source and date on every value, is the honest way to compare them.
Capabilities
Feature-by-feature on the axes that matter for llm observability. “-” means undocumented, not absent.
What each one is
The product in its own terms, so the numbers below have context.
Arize Phoenix
A self-hosted platform that traces and evaluates language model application behavior using OpenTelemetry instrumentation, enabling teams to debug, optimize, and monitor LLM performance.
Braintrust
Braintrust provides real-time observability for AI agents in production. It enables teams to inspect traces and tool calls, automatically discover patterns and issues, run experiments to evaluate quality, and continuously iterate on agent performance.
Pricing
List pricing as published by each vendor, with the date we read it. Always verify at the source before you buy.
Braintrust
Pricing not documented yet.
Platform & deployment
Where each product runs and how it can be hosted. A dash means undocumented, not unsupported.
Integrations
What each product connects to. Counts come from the vendor's own integration directory where one exists.
- OpenAI
- Anthropic
Arize Phoenix
- LlamaIndex
- AWS Bedrock
- Vertex AI
- Claude Code
- Cursor
- OpenLLMetry
- OpenTelemetry
- OpenInference
- Gemini
- Google Vertex AI
- Google Gemini
- Together AI
- Fireworks
- NVIDIA NIM
- LiteLLM
- LangChain
- Traceloop
Braintrust
Arize Phoenix or Braintrust: which one depends on you
A composite score cannot know your constraints. Describe them and both get re-weighted against what you actually need, with the evidence behind every position.
Free to run, no account needed to start. How the evaluation works
Comparison generated from independently-sourced facts. Every value links to its source and retrieval date. See the method.