Arize vs Evidently AI (2026): Pricing, Features & Which to Choose

Who comes out ahead

Based only on the facts in our directory. The right pick still depends on the job you need done.

Lower starting price
Not comparable
Not comparable: Arize does not list a price
Free plan
Evidently AI
Only Evidently AI has one
Higher rating
Arize
4.2 against 3.7
Same job?
Yes
Both are AI Infrastructure & Agent Tooling tools

Side by side

Compared on	Arize	Evidently AI
Our rating	4.2Better	3.7
Starts at	Not listed	Free
Free plan	No	YesBetter
Category	AI Infrastructure & Agent Tooling	AI Infrastructure & Agent Tooling
Plans	See pricing	Free
Key features	Started in traditional ML drift and performance monitoring before expanding to LLMs Open-source Arize Phoenix framework for generative AI observability LLM evaluation and prompt versioning through a Prompt Hub Tracing built for multi-step, conversational agent applications $131M raised, valued at over $1 billion as of its February 2025 Series C	LLM-as-a-Judge evaluation methodology 100+ built-in metrics - hallucinations, toxicity, PII detection, retrieval quality Synthetic data generation for edge-case and adversarial testing Continuous monitoring dashboards tracking quality drift Open-source under Apache 2.0, 7,500+ GitHub stars
Pros	Covers both traditional ML monitoring and generative AI evaluation in one platform Open-source Phoenix framework gives a free, inspectable starting point before adopting the full platform Billion-dollar valuation and $131M raised signal real staying power	Fully open-source (Apache 2.0) - no vendor lock-in or opaque pricing Real, notable enterprise adoption (DeepL, Wise, Plaid, Databricks) Covers the full lifecycle - evaluation, synthetic testing, and ongoing monitoring
Cons	Enterprise pricing isn't published, so budgeting requires a sales conversation Broad scope spanning classic ML and generative AI can mean more setup than a single-purpose LLM tool Competes directly against well-funded peers like Braintrust and LangSmith in a crowded observability market	Open-source self-hosting requires real technical setup and maintenance No managed/hosted pricing tier detailed on the page reviewed Best suited to teams with dedicated MLOps or ML infrastructure capacity
Company	Arize AI, founded 2020	Evidently AI

Prices come from each vendor's pricing page, last checked 20260826. Check the vendor before you buy.

FAQ

Questions people ask

Is Arize better than Evidently AI?

In our reviews Arize scores 4.2 and Evidently AI scores 3.7. The better pick depends on the job. Arize: Grew from traditional ML monitoring into a $1B+ AI engineering platform for evaluating agents in production. Evidently AI: LLM-as-a-Judge evaluation with 100+ built-in metrics for hallucinations, toxicity, and PII - open-source, 7,500+ GitHub stars, used by DeepL, Wise, Plaid, and Databricks.

Which is cheaper, Arize or Evidently AI?

Arize: see pricing. Evidently AI: free.

Do Arize and Evidently AI have free plans?

Only Evidently AI has a free plan.

More comparisons

Arize compared with

All Arize alternatives

Evidently AI compared with

All Evidently AI alternatives