8 Best OpenAI Evals Alternatives in 2026 (Open Source)
OpenAI Evals — Evals is a framework for evaluating LLMs and LLM systems, and an open-source registry of benchmarks..
These 8 open-source tools do the same job. They are ordered by how closely they match OpenAI Evals, with live GitHub data so you can see which projects are actively maintained.
| Tool | GitHub stars | Stars / 30d | Last commit |
|---|---|---|---|
| OpenAI Evals(original) | 19.5k | +231 | 2026-04-14 |
| DeepEval | 18.5k | +676 | 2026-09-29 |
| Ragas | 15.9k | +443 | 2026-02-24 |
| Promptfoo | 25.6k | +1,117 | 2026-09-30 |
| Langfuse | 35.2k | +1,821 | 2026-09-30 |
| phoenix | 11.7k | +418 | 2026-09-30 |
| langwatch | 4.9k | +277 | 2026-09-30 |
| Agenta | 4.8k | +131 | 2026-09-30 |
| UpTrain | 2.4k | +4 | 2024-07-29 |
1. DeepEval
The LLM Evaluation Framework
What sets it apart: Most comprehensive open-source LLM eval framework with 30+ research-backed metrics including agentic, RAG, multi-turn, MCP, and multimodal — vs Ragas (RAG-only) or custom eval scripts
Best for: Teams needing comprehensive LLM/agent evaluation pipelines; CI/CD integration for LLM app quality gates; RAG pipeline evaluation and optimization
2. Ragas
Supercharge Your LLM Application Evaluations 🚀
What sets it apart: vs manual LLM evaluation: Purpose-built evaluation framework with both LLM-based and traditional metrics, automated test generation, and seamless integration with popular LLM frameworks
Best for: Evaluating RAG pipeline quality with automated metrics; Generating comprehensive test datasets for LLM apps; Building continuous evaluation feedback loops
3. Promptfoo
Test your prompts, agents, and RAGs. Red teaming/pentesting/vulnerability scanning for AI. Compare performance of GPT, Claude, Gemini, Llama, and more. Simple declarative configs with command line and
What sets it apart: Unlike LangSmith (production observability) or Langfuse (logging), promptfoo is the only open-source tool combining eval + red teaming + CI/CD code scanning — now backed by OpenAI while remaining fully MIT-licensed
Best for: Teams hardening LLM apps against prompt injection and jailbreaks with automated red teaming; Engineering teams adding LLM eval regression tests to CI/CD pipelines
4. Langfuse
🪢 Open source LLM engineering platform: LLM Observability, metrics, evals, prompt management, playground, datasets. Integrates with OpenTelemetry, Langchain, OpenAI SDK, LiteLLM, and more. 🍊YC W23
What sets it apart: Unlike LangSmith (LangChain-specific) or Helicone (proxy-based), Langfuse is fully open-source, framework-agnostic, and self-hostable, combining tracing, prompt management, evaluations, and datasets in a single platform built on ClickHouse for scalable production use.
Best for: Teams operating production LLM applications who need tracing, prompt management, and evaluation in one platform; Organizations requiring self-hosted LLM observability for data privacy compliance
5. phoenix
AI Observability & Evaluation
What sets it apart: Full-stack AI observability (tracing + eval + datasets + prompt management) in one open-source platform — vs LangSmith which is closed-source and LangChain-specific
Best for: Debugging and monitoring LLM applications in production; Systematic prompt engineering and experiment tracking
6. langwatch
The platform for LLM evaluations and AI agent testing
What sets it apart: Unified platform combining agent simulation, evaluation, observability, and prompt optimization with OpenTelemetry-native design — vs separate tools for tracing (Langfuse), eval (DeepEval), and prompt management
Best for: Teams wanting eval + observability + prompt management in one tool; Agent simulation testing before production deployment; Organizations needing OpenTelemetry-native LLM observability
7. Agenta
The open-source LLMOps platform: prompt playground, prompt management, LLM evaluation, and LLM observability all in one place.
What sets it apart: Unified open-source LLMOps platform combining prompt playground, version control, 20+ evaluators, and OTel-native observability in one tool — vs separate tools for each
Best for: Teams needing integrated prompt management + evaluation + observability; Product teams collaborating with SMEs on prompt engineering; Organizations wanting open-source LLMOps alternative
8. UpTrain
UpTrain is an open-source unified platform to evaluate and improve Generative AI applications. We provide grades for 20+ preconfigured checks (covering language, code, embedding use-cases), perform ro
What sets it apart: vs generic eval tools: 20+ preconfigured evaluations with customizable prompts, few-shot examples, and scenario descriptions — all running locally for data privacy with root cause analysis on failures
Best for: RAG system evaluation and quality assurance; LLM application testing before production deployment; Safety and security testing for prompt injection vulnerabilities