Test how well your language model performs on specific tasks before deploying it to users.
Create private benchmarks using your own proprietary data to measure model quality without sharing data publicly.
Compare performance across different model versions or configurations to pick the best one for your application.
Build evaluations that use another AI model to automatically grade whether outputs are correct or helpful.
Requires OpenAI API key and potentially Snowflake credentials for full functionality.
OpenAI Evals is a framework for evaluating large language models (LLMs), AI systems that generate text, and an open-source registry of benchmark tests for measuring their capabilities. An "eval" in this context is a structured test that runs a model against a set of inputs and measures how well its outputs match expected results. The project serves two purposes. First, it provides an existing library of benchmarks that test different capabilities of language models. Second, it gives developers a framework to write their own custom evaluations for use cases specific to their application, including private evals that use proprietary data without exposing it publicly. Custom evals can be built in two ways: model-graded evals, where another language model judges whether the output is correct (these are currently accepted as contributions), or evals with custom Python code (currently not accepted as community submissions). For basic evals, no coding is required, you provide data in JSON format and specify parameters in a YAML configuration file. To run evals, you need an OpenAI API key and Python 3.9 or later. The eval registry data is stored using Git LFS (Large File Storage), a Git extension for tracking large binary files, which needs to be fetched separately after cloning the repository. Results can optionally be logged to a Snowflake database. An interactive dashboard version is also available directly in the OpenAI platform without needing this codebase.
Generated 2026-05-18 · Model: sonnet-4-6 · Verify against the repo before relying on details.