{"id":18636,"date":"2025-12-09T21:02:46","date_gmt":"2025-12-09T21:02:46","guid":{"rendered":"https:\/\/www.comet.com\/site\/?page_id=18636"},"modified":"2026-09-03T16:37:49","modified_gmt":"2026-09-03T16:37:49","slug":"langfuse-vs-opik","status":"publish","type":"page","link":"https:\/\/www.comet.com\/site\/products\/opik\/compare\/langfuse-vs-opik\/","title":{"rendered":"Langfuse vs. Opik"},"content":{"rendered":"\n
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The Best Open-Source LLM Evaluation Platform in 2026: Opik vs. Langfuse<\/strong><\/strong><\/h1>\n\n\n\n

Last updated: 2026-07-30<\/em><\/p>\n\n\n\n

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\u2728 The short answer:<\/strong> Langfuse is a good tool for seeing what your AI is doing, and it is free to run yourself, same as Opik. The question is what happens after you spot a bad answer. With Langfuse, fixing it is manual. Opik ships the optimization layer: six autonomous prompt optimization algorithms, Ollie for AI-powered diagnostics and actual code-fix recommendations, and Test Suites to automate evaluation with practical pass\/fail assertions. Choose Langfuse if its MIT licence, praised developer UX, and deep prompt management are the priority. Choose Opik if you need to go beyond finding problems and actually fix them.<\/p>\n<\/div>\n<\/div>\n\n\n\n

Both tools trace, evaluate, and monitor LLM and agent applications. Opik is an open-source LLM and agent evaluation and observability platform built by Comet. Langfuse is an open-source LLM engineering platform with solid fundamentals: tracing, prompt management, evaluation, and custom dashboards. The practical difference is not whether you can self-host, both let you, free, but what happens after you find a problem. Langfuse\u2019s strongest focus is on logging and analysis: it gives you clear visibility into what your AI is doing. Opik goes further on the improvement side, shipping autonomous prompt optimization, Ollie for AI-powered diagnostics, Test Suites for automated evaluation, and multimodal evaluation as part of the product. Where Langfuse\u2019s prompt improvement workflow is largely manual, Opik\u2019s optimization layer is built in. On enterprise readiness, Opik\u2019s open-source and enterprise versions share the same core product, enterprise plans add flexible deployment options, identity and access management, and compliance certifications, and run on the Comet platform, which has been proven at scale by organizations including Netflix, Uber, Autodesk, Etsy, NatWest, and Stellantis. That makes it straightforward to start on the OSS version and upgrade to enterprise when you\u2019re ready.<\/p>\n<\/div>\n<\/div>\n\n\n\n

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What are the best open-source alternatives to Langfuse in 2026?<\/h2>\n\n\n\n

TThe platforms teams most often evaluate alongside Langfuse are Opik, LangSmith, Weights & Biases Weave, and Arize Phoenix. Listed with public GitHub footprint as of 2026-08-13, which is a reasonable proxy for how many teams can inspect and run the code themselves:<\/p>\n\n\n\n