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Launched 2023 Β· Verified Oct 2, 2026

Ragas

Verified Oct 2, 2026 Active
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Open-source Python toolkit that scores RAG and agent apps with LLM-based metrics and generates synthetic test sets.

ragevaluationllm metricstest generationopen sourcepythonFree

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macOS Β· Windows Β· Linux
Screenshot of the Ragas website
#3321
docs.ragas.io as we captured it β€” our own screenshot, not the vendor’s press image.

Pricing

Pricing model
100% Free

The library is free under Apache-2.0 and installs with pip. You pay your own LLM provider for the judge calls the metrics make. The company mentions enterprise features by contact only, with no price published.

Use tool β†—
Overview

About Ragas

Ragas is a Python library for evaluating applications built on retrieval-augmented generation and agents. It ships metrics such as faithfulness, answer relevancy, context precision and context recall, computed by an LLM judge or by classic measures, and can generate test datasets from your own documents when you have none. It plugs into LangChain, LlamaIndex and common observability tools, so scores can follow a pipeline from development into production. The project is Apache-2.0 licensed and maintained by Vibrant Labs, which also offers enterprise features on request.

Platforms
macOS Β· Windows Β· Linux
API
No
Last verified
Oct 2, 2026

Verified sources

  • Vendor site: open-source RAG evaluation with metrics, synthetic data and online monitoring; enterprise by contact; founders and companyragas.io β†—
  • GitHub repository: Apache-2.0 licence, created May 2023, homepage docs.ragas.iogithub.com β†—
  • Vibrant Labs is a Y Combinator W24 company based in San Franciscoycombinator.com β†—
Fact check

Is Ragas legit?

We don’t label tools safe or unsafe. Below are the records we checked ourselves, each with the date we read it.

Last checked
Oct 2, 2026The site answered
On the market since
2023The vendor's own material, read by us
Operated by
Vibrant Labs, United StatesOur research, card verified Oct 2, 2026

How we collect these records

Editorial verdict

Pros & cons of Ragas

medium confidence

Ragas is a common first choice for putting numbers on a RAG pipeline: it is free, has the usual metric names everyone recognises, and drops into existing Python code. It fits engineers who want repeatable scores in CI or notebooks. Expect to spend on judge-model calls, and treat LLM-judged scores as indicators, not ground truth.

Pros

  • Free Apache-2.0 library with a large community
  • Metrics cover faithfulness, relevancy and context precision and recall
  • Synthetic test-set generation helps when no labelled data exists
  • Integrates with LangChain, LlamaIndex and observability tools

Cons

  • Metric scores come from an LLM judge, so they cost tokens and vary between judge models
  • No published price for the commercial online monitoring side
  • Library APIs have changed across minor versions, so pin the version you tested with

Best for

  • Engineers measuring retrieval and answer quality of a RAG pipeline before release
  • Teams that need synthetic test questions built from their own documents

Not for

  • Non-developers who want a point-and-click evaluation dashboard
  • Teams that need a fully hosted tracing and monitoring service with a published price

Watch out: Each metric run calls an LLM, so scoring a large test set can cost real money on your provider bill, and the GitHub repository now lives under the vibrantlabsai organization rather than the older explodinggradients one.

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