{"id":19847,"date":"2026-05-12T15:33:43","date_gmt":"2026-05-12T15:33:43","guid":{"rendered":"https:\/\/www.comet.com\/site\/?page_id=19847"},"modified":"2026-05-12T15:33:44","modified_gmt":"2026-05-12T15:33:44","slug":"fiddler-vs-opik","status":"publish","type":"page","link":"https:\/\/www.comet.com\/site\/products\/opik\/compare\/fiddler-vs-opik\/","title":{"rendered":"Fiddler vs. Opik"},"content":{"rendered":"\n
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Fiddler vs. OPIK<\/h1>\n\n\n\n

Opik & Fiddler: AI Observability Platform Comparison<\/h2>\n\n\n\n

Compare Opik and Fiddler to understand how each tool supports observability for AI applications.<\/p>\n<\/div>\n\n\n\n

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Feature Comparison: Opik vs. Fiddler<\/h2>\n\n\n\n

Fiddler and Opik both provide visibility into AI systems, but they focus on different parts of the lifecycle. Fiddler is an enterprise-first AI observability and security platform designed to monitor model performance, detect risks, and enforce governance across LLM applications. It emphasizes production monitoring, explainability, and compliance at scale. Opik is built for developers working on GenAI applications, with tools for tracing, agent evaluation, experimentation, and prompt, agent, and workflow optimization.<\/p>\n<\/div>\n\n\n\n

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Feature<\/th>Details<\/th>Opik<\/th>Fiddler<\/th><\/tr><\/thead>
Open Source<\/td>Open-source  and fully transparent with enterprise scalability<\/td>\"checkmark\"Yes<\/td>\"cross\"No<\/td><\/tr>
Observability<\/strong><\/td><\/td><\/td><\/td><\/tr>
GenAI Tracing<\/td>Trace any AI application through a simple function decorator and 40+ integrations<\/td>\"checkmark\"Yes<\/td>\"checkmark\"Yes<\/td><\/tr>
Agent Tracking <\/td>Track complete agent execution with agent graph visuals, nested views, and tool use<\/td>\"checkmark\"Yes<\/td>\"checkmark\"Yes<\/td><\/tr>
Evaluation<\/strong><\/td><\/td><\/td><\/td><\/tr>
Online Evaluation<\/td>Configure flexible online evaluation with LLM-as-a-judge<\/a> or custom code metrics to evaluate live runs<\/td>\"checkmark\"Yes<\/td>\"checkmark\"Yes<\/td><\/tr>
Expert Annotation UI<\/td>Define feedback schemas, assign users to annotation queues, and track progress with a dedicated UI.<\/td>\"checkmark\"Yes<\/td>
\"cross\"No<\/td><\/tr>
Experimentation<\/td>Run evaluations over datasets with custom & built-in metrics supporting RAG, agentic, multimodal, &conversational use cases<\/td>\"checkmark\"Yes<\/td>\"checkmark\"Yes<\/td><\/tr>
Development<\/strong><\/td><\/td><\/td><\/td><\/tr>
Automated Agent Optimization<\/td>Automatically refine entire agents & prompts<\/td>\"checkmark\"Yes<\/td>\"cross\"No<\/td><\/tr>
Prompt Playground<\/td>Test & refine prompts and outputs from LLMs<\/td>\"checkmark\"Yes<\/td>\"cross\"No<\/td><\/tr>
Production<\/strong><\/td><\/td><\/td><\/td><\/tr>
Production Monitoring<\/td>Production-scale LLM observability<\/a> with metrics dashboards, alerts, and cost, latency, and usage tracking<\/td>\"checkmark\"Yes<\/td>\"checkmark\"Yes<\/td><\/tr>
Guardrails<\/td>Built-in guardrails for PII and restricted topics, as well as custom guardrails<\/td>\"checkmark\"Yes<\/td>\"checkmark\"Yes<\/td><\/tr><\/tbody><\/table><\/figure>\n\n\n\n
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These Are Just the Highlights<\/h2>\n\n\n\n

Explore the full range of Opik’s features and capabilities in our developer documentation or check out the full repo on GitHub.<\/p>\n\n\n\n

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GitHub<\/a><\/div>\n\n\n\n
Documentation<\/a><\/div>\n<\/div>\n<\/div>\n\n\n\n
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Opik’s Advantages<\/h2>\n\n\n\n

Opik is designed for teams that need to continuously improve system performance through evaluation and iteration.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Built for Improving AI Systems<\/h3>\n\n\n\n

Opik is designed to help teams improve AI systems, with built-in evaluation and optimization workflows.<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Native Optimization Workflows<\/h3>\n\n\n\n

Opik provides prompt, tool, and agent optimization out of the box, enabling systematic improvement without external tooling.<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Development & Production in One Platform<\/h3>\n<\/div>\n\n\n\n

Support for prompt iteration, evaluation, experimentation, and monitoring in a single workflow, rather than separating development and production tooling.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Fiddler’s Advantages<\/h2>\n\n\n\n

Fiddler is designed for teams that need centralized monitoring and risk control across deployed systems.<\/p>\n<\/div>\n\n\n\n

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Strong Enterprise Monitoring and Governance<\/h3>\n\n\n\n

Fiddler is designed for organizations that need centralized visibility, risk detection, and compliance across AI systems.<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Advanced Explainability and Root Cause Analysis<\/h3>\n\n\n\n

Fiddler provides detailed insights into model behavior, helping users understand why outputs are generated and diagnose issues at scale.<\/p>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Built for Responsible AI at Scale<\/h3>\n\n\n\n

With guardrails, safety metrics, and policy enforcement, Fiddler helps teams deploy AI systems that meet strict regulatory and security requirements.<\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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\"pattern<\/a><\/figure>\n<\/div>\n\n\n\n

“Opik being open-source was one of the reasons we chose it. Beyond the peace of mind of knowing we can self-host if we want, the ability to debug and submit product requests when we notice things has been really helpful in making sure the product meets our needs.\u201d<\/p>\n\n\n\n

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\"Jeremy<\/figure>\n\n\n\n
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Jeremy Mumford<\/strong><\/p>\n\n\n\n

Lead AI Engineer, Pattern<\/a><\/strong><\/p>\n<\/div>\n<\/div>\n<\/div>\n<\/div>\n\n\n\n

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Ready to Upgrade Your AI Development Workflows?<\/h2>\n\n\n\n

Join the growing number of developers who’ve turned to Opik for superior performance, flexibility, and advanced features when building AI applications.<\/p>\n\n\n\n

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Create Free Account<\/a><\/div>\n\n\n\n
Contact Sales<\/a><\/div>\n<\/div>\n<\/div>\n<\/div>\n","protected":false},"excerpt":{"rendered":"

Feature Comparison: Opik vs. Fiddler Fiddler and Opik both provide visibility into AI systems, but they focus on different parts of the lifecycle. Fiddler is an enterprise-first AI observability and security platform designed to monitor model performance, detect risks, and enforce governance across LLM applications. It emphasizes production monitoring, explainability, and compliance at scale. Opik […]<\/p>\n","protected":false},"author":140,"featured_media":19854,"parent":17633,"menu_order":0,"comment_status":"closed","ping_status":"closed","template":"wp-custom-template-pages-dark","meta":{"customer_name":"","customer_description":"","customer_industry":"","customer_technologies":"","customer_logo":"","footnotes":""},"coauthors":[127],"class_list":["post-19847","page","type-page","status-publish","has-post-thumbnail","hentry"],"yoast_head":"\nFiddler vs. Opik: AI Observability & Evaluation Comparison<\/title>\n<meta name=\"description\" content=\"Compare Opik and Fiddler's feature set, to understand how each platform supports AI observability & evaluation.\" \/>\n<meta name=\"robots\" content=\"index, follow, max-snippet:-1, max-image-preview:large, max-video-preview:-1\" \/>\n<link rel=\"canonical\" href=\"https:\/\/www.comet.com\/site\/products\/opik\/compare\/fiddler-vs-opik\/\" \/>\n<meta property=\"og:locale\" content=\"en_US\" \/>\n<meta property=\"og:type\" 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