Python data quality library that lets teams write declarative Expectations as unit tests for their data and generate validation reports.
evidentlyai/evidently
Open-source Python framework to evaluate, test and monitor ML and LLM systems, with 100+ built-in metrics and drift detection.
- Stars
- 7,999
- Forks
- 954
- Open issues
- 345
- Last commit
- 23 days ago
What is it?
Evidently is an open-source Python library for evaluating, testing, and monitoring machine learning and LLM systems, from experiments through production. It covers tabular and text data, with evaluations for predictive tasks such as classification and regression, and generative tasks such as RAG and LLM output quality.
The core workflow uses Reports, which compute and summarize metrics, and Test Suites, which add pass/fail conditions on top of a Report for regression testing, CI/CD checks, or data validation. Reports can be viewed in Python, or exported as JSON, a Python dictionary, or HTML. Data drift detection, data quality checks, and LLM judges are among the built-in options, and custom metrics can be written in Python.
For ongoing monitoring, Evidently provides a web UI that tracks metrics and test results over time. It can be self-hosted from the open-source package, or used through the managed Evidently Cloud service.
Key features
- 01Built-in metrics for data drift, data quality, classification, regression, ranking, and recommendations.
- 02LLM evaluation with text descriptors and LLM-as-a-judge evaluators.
- 03Reports and Test Suites with pass/fail conditions for CI/CD and regression checks.
- 04Export results as HTML, JSON, or Python dictionaries.
- 05Self-hosted monitoring UI for tracking metrics over time.
Use cases
- Detecting whether production input data has drifted from training data.
- Running regression tests on LLM or RAG outputs in a CI pipeline.
- Validating data quality before model training or batch pipelines.
- Monitoring a deployed ML model's performance over time on a dashboard.
Quick start
- 1
Install Evidently from PyPI
pip install evidently - 2
Run the Evidently UI with demo projects
evidently ui --demo-projects all - 3
Open localhost:8000 in your browser to access the UI
Things to know
- Some advanced features such as alerting, dataset and user management, and no-code evals are only in the paid-tier Evidently Cloud, not the open-source version.
Topics
FAQ
- What is evidently?
- Open-source Python framework to evaluate, test and monitor ML and LLM systems, with 100+ built-in metrics and drift detection. Evidently is an open-source Python library for evaluating, testing, and monitoring machine learning and LLM systems, from experiments through production. It covers tabular and text data, with evaluations for predictive tasks such as classification and regression, and generative tasks such as RAG and LLM output quality.
- Is evidently free to use? What license does it have?
- evidently is open source under the Apache-2.0 license. Check the license terms before using it in commercial products.
- Is evidently still maintained?
- Actively maintained. The last commit to evidently was on Sep 29, 2026.
- What can I use evidently for?
- Detecting whether production input data has drifted from training data. Running regression tests on LLM or RAG outputs in a CI pipeline. Validating data quality before model training or batch pipelines. Monitoring a deployed ML model's performance over time on a dashboard.
- How do I install evidently?
- Install Evidently from PyPI: pip install evidently Run the Evidently UI with demo projects: evidently ui --demo-projects all Open localhost:8000 in your browser to access the UI
- Where can I get evidently?
- The source code and installation instructions are on GitHub: https://github.com/evidentlyai/evidently
Summary generated by AI from the project's README. GitHub stats refresh daily.
Related projects
Open-source AI training tracking and visualization platform for logging metrics, hyperparameters and hardware stats, with cloud or self-hosted deployment.
A free, self-paced 9-week online course covering MLOps: experiment tracking, orchestration, deployment, monitoring and best practices.
A Python library for building and serving AI model inference APIs, multi-model pipelines and LLM apps, with Docker and Kubernetes deployment.
A public leaderboard ranking LLMs by how often they hallucinate when summarizing short documents, scored with Vectara's HHEM evaluation model.
Open-source Python platform for building ML and AI workflows as pipelines that run on your own or cloud infrastructure, from training models to agents.