Evidently AI

Evidently AI is an open-source Python library and cloud platform for evaluating, testing and monitoring machine learning models and LLM applications. Data scientists use it to check data drift, model quality and LLM output quality with ready-made metrics.

The library ships many built-in metrics and test presets for classification, regression, ranking, data drift and LLM outputs, including LLM-as-judge evaluators. Reports render as interactive HTML or JSON.

Evidently Cloud adds dashboards, tracing, synthetic test data and team collaboration. The open-source library is free, and the cloud has a free tier plus paid plans.