Phoenix

Name: Phoenix
Brand: Phoenix
Price: 50 USD

Claim this tool

Evaluate, experiment, and optimize AI products in real time with open-source LLM tracing.

From $50/mo, billed monthly (free plan available)

Freemium Developer Tools Analytics Debugging AI & Automation

Visit Website

Freemium Visit Website

Tracked since 2026

The Bottom Line

Updated Oct 13, 2026

Price: From $50/mo, billed monthly (free plan available). Compare plans

Key facts

Open-source LLM tracing and evaluation platform.
Provides real-time visibility, debugging, and optimization for AI products.
Features interactive prompt playgrounds, evaluation libraries, and dataset visualization.

Pros

Open-source and self-hostable, offering flexibility and no vendor lock-in.
Provides deep observability into LLM behavior and decision-making.
Facilitates rapid experimentation and iteration with interactive playgrounds.
Supports both automated and human feedback for comprehensive evaluations.
Strong community support and integrations with popular LLM frameworks.

Cons

Advanced features like dedicated support and custom data limits are only available in higher-tier paid plans.
The free SaaS tier has limited trace spans and ingestion volume.
Requires some technical expertise for self-hosting and full utilization.

What is Phoenix?

Phoenix is an open-source platform designed for evaluating, experimenting with, and optimizing AI products, specifically Large Language Models (LLMs). It provides comprehensive LLM observability by allowing users to trace, visualize, and debug LLM applications in real-time. Built on OpenTelemetry, Phoenix offers seamless data collection, transparency, and avoids vendor lock-in. The tool is ideal for AI engineers, developers, and data scientists working with LLMs who need to understand model behavior, identify failures, and improve performance. It helps in debugging complex LLM decision-making, flagging poor responses, and troubleshooting issues related to retrieval and tool execution. Phoenix aims to integrate observability directly into the development process, encouraging continuous improvement of LLM applications before and after deployment. Key functionalities include interactive prompt playgrounds for iteration, streamlined evaluation libraries with pre-built templates and human feedback integration, and dataset clustering/visualization to uncover performance issues using embeddings. Its open-source nature and self-hostable option provide flexibility and control for small teams to large enterprises.

Available on: Web

Data compiled by Toolradar Pricing checked Oct 13, 2026 · How we evaluate

Source phoenix.arize.com

Preview

Key Features

OpenTelemetry (OTEL) for seamless setup and data collection
Application tracing for total visibility into LLM app data
Interactive prompt playground for prompt and model iteration
Streamlined evaluation and annotation library with pre-built templates
Dataset clustering and visualization using embeddings
Self-hostable with no feature gates or restrictions
Integration with various LLM tools and frameworks
Online and offline evaluations, including LLM as judge and code evals

Pricing Plans

Pricing checked Oct 13, 2026. Source: phoenix.arize.com/pricing, read Oct 13, 2026

Phoenix plans and prices, checked October 2026
Plan	Price	Details
Phoenix Small teams and smaller data	Free & open source	Trace spans user managed Ingestion volume user managed Projects user managed +2 more Show less Retention user managed Support add-on dedicated support
AX Free	Free	25k trace spans per month 1 GB ingestion volume per month 7 days retention +4 more Show less Alyx (Arize agent) Online evals Product observability (monitors & custom metrics) Community support
AX Pro	$50 / month	50k trace spans per month 10 GB ingestion volume per month 15 days retention +4 more Show less Everything in AX Free Higher rate limits Longer retention Email support
AX Enterprise	Custom	Custom trace spans Custom ingestion volume Custom projects +11 more Show less Configurable retention Everything in AX Pro Dedicated support Uptime SLA Custom data limits SOC2 reports and HIPPA Training sessions DataFabric Connect Self-Hosting add-on Data residency Multi-region deployments

Calculate your cost View full pricing

Is Phoenix worth the price?

Good value

Phoenix offers a very generous free tier with its open-source solution and a substantial free tier for AX, making it highly accessible.

The AX Pro tier at $50/month provides good value for growing teams needing more capacity. This pricing structure is best for individual developers and small to medium-sized teams focused on AI product evaluation and optimization.

Hidden Costs & Gotchas

Overage fees for exceeding trace spans/ingestion

Add-ons for dedicated support

Self-hosting is an add-on

Full Phoenix pricing: every plan, hidden costs and alternatives

How Phoenix's pricing compares

At $50/mo, billed monthly, Phoenix is mid-range of its 4 comparable direct competitors ($19 to $100/mo across the set).

Comet ML

$19

LangSmith

$39

Phoenix

$50

Weights & Biases

$60

Helicone

$100

Entry paid plan, monthly price, billed monthly. Pricing checked Oct 13, 2026.

Phoenix by the numbers

Toolradar data: Phoenix's entry paid plan ($50/mo, billed monthly) ranks #29 of 35 for price among the Debugging tools with a verified entry price and no stated unit, where the median is $20/mo. As of Oct 2026.

Phoenix compared with 93 Debugging tools on Toolradar, as of Oct 2026
Metric	Phoenix	Peer median	Position (1 is best)
Entry paid plan	$50/mo, billed monthly	$20/mo	#29 of 35 tools with no stated price unit, verified price
Free plan	Yes	89% have one	n/a
Integrations listed	1	2	#17 of 24 (joint) tools with at least one integration recorded

Each position is counted among the tools that have data for that row, as noted under it. A lower entry price ranks higher; prices are read on vendor pages and compared only with tools priced on the same basis. All Debugging data · How we compute this. Advertising and placement fees are not inputs to any position.

Cite this: Toolradar, “Phoenix by the numbers”, Oct 2026.

Reviews

Improve Your Thinking Patterns Using ChatGPT cover

$99 Free with your review

Review Phoenix, get a free AI guide

Share your experience and we will send you Improve Your Thinking Patterns Using ChatGPT, free.

Write a review

Best Phoenix Alternatives

Top alternatives based on features, pricing, and user needs.

Weights & Biases Freemium

Track, compare, and share ML experiments and models

4.6

Comet ML Paid

Machine learning experiment tracking platform

4.3

Helicone Freemium

Build reliable AI apps with Helicone: AI Gateway & LLM Observability for debugging, routing, and analysis.

LangSmith Freemium

Debug, monitor, and optimize your LLM applications and AI agents with comprehensive observability.

OpenLLMetry Freemium

Open-source observability for LLMs using OpenTelemetry.

See all developer tools →

Still deciding?

Most buyers shortlist 2 or 3 tools before committing. Pull a side-by-side comparison or browse the full alternatives shortlist below.

Phoenix vs Weights & Biases Head-to-head: features, pricing, who wins Phoenix vs Comet ML Head-to-head: features, pricing, who wins Phoenix vs Helicone Head-to-head: features, pricing, who wins

Explore More

Phoenix FAQ

How does Phoenix help in optimizing AI products?

Phoenix optimizes AI products by providing comprehensive LLM observability, allowing users to trace, visualize, and debug LLM applications in real-time. It facilitates rapid experimentation with interactive prompt playgrounds and streamlines evaluation through libraries and human feedback integration.

Which teams benefit most from using Phoenix?

Phoenix is ideal for AI engineers, developers, and data scientists working with LLMs. These teams can use it to understand model behavior, identify failures, debug complex decision-making, and improve the performance of their LLM applications.

How does Phoenix compare to LangSmith?

Phoenix, like LangSmith, offers tools for observing and debugging LLM applications. However, Phoenix distinguishes itself by being open-source and self-hostable, which provides flexibility and helps avoid vendor lock-in.

What kind of limitations should users be aware of with Phoenix?

Users should note that advanced features, such as dedicated support and custom data limits, are reserved for higher-tier paid plans. The free SaaS tier also has limitations on trace spans and ingestion volume, and self-hosting requires some technical expertise.

How is Phoenix priced?

Phoenix is available on a free tier, which offers basic usage. For users requiring more extensive usage and additional features, paid plans are available.

Can Phoenix integrate with existing LLM development workflows?

Yes, Phoenix is built on OpenTelemetry, which allows for seamless data collection and transparency. It also boasts strong community support and integrations with popular LLM frameworks, making it adaptable to various development processes.

How does Phoenix assist in debugging LLM applications?

Phoenix assists in debugging by allowing users to trace and visualize LLM applications in real-time. It helps in identifying and troubleshooting issues related to retrieval and tool execution, flagging poor responses, and understanding complex LLM decision-making.

How does Phoenix pricing compare with other Debugging tools?

Phoenix's entry paid plan ($50/mo, billed monthly) ranks #29 of 35 for price among the Debugging tools with a verified entry price and no stated unit, where the median is $20/mo. Prices are read on each vendor's own pricing page and compared only with tools priced on the same basis. Source: Toolradar, Oct 2026.

Source: phoenix.arize.com

Guides & Articles

Best LLM Observability Tools in 2026

Features Phoenix

Best AI Prompt Management Tools in 2026

Features Phoenix

Best Prompt Management & PromptOps Tools 2026

Expert guide