Free AI Tools to Monitor & Evaluate LLM Apps

The best free AI tools to monitor & evaluate LLM apps, ranked by our checks. Last checked 18 Oct 2026.

Ranked AI tools you can use to monitor & evaluate LLM apps. Each listing shows verified free-tier details from the vendor pricing page; picks require at least one month of free access (free plan, monthly credits, or a trial of 30+ days).

21 free tools

Each with its last-checked date

Braintrust
Evals and observability platform for AI products.
Free forever, Free plan for evals and logging
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Arize Phoenix
Open-source LLM tracing and evaluation.
Free forever, Open-source and free cloud tier
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Langfuse
Open-source LLM observability and evals.
Free forever, Free Hobby plan; open source self-host
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Helicone
Open-source LLM observability and gateway.
Free forever, Monthly requests
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Grafana Cloud
Observability platform with AI assistant.
Free forever
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Agenta
Open-source LLMOps platform for prompts and evals.
Free forever
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Confident AI
LLM evaluation platform built on DeepEval.
Free forever
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Logo.com
Free AI logo maker and brand kit.
Free forever, Free logo maker
AI Design
AI Design
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Dify
Open LLM app platform for agents, RAG workflows, and observability.
Free forever, Sandbox (free): 200 message credits, 5 apps, 1 member
AI Agents & Automation
AI Agents & Automation
Free accountTry
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LangSmith
Observability, evals and deployment for LLM agents.
Free forever, Free Developer plan: 5k traces per month
AI Agents & Automation
AI Agents & Automation
Free accountTry
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Better Stack
Uptime monitoring, logs and incident management.
Free forever
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Laminar
Open-source observability for AI agents.
Free forever
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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AgentOps
Observability and evals for AI agents.
Free forever
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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PromptLayer
Prompt management and LLM observability.
Free forever
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Sentry
Error monitoring with AI-powered debugging.
Free forever, Free Developer plan
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Weights & Biases (CoreWeave Forge)
ML experiment tracking and LLM evaluation, now part of CoreWeave Forge (wandb.ai redirects there).
Free forever, Free $0/mo plan for personal development: evaluations, tracing, experiment tracking, registry
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Portkey
AI gateway, guardrails and observability.
Free forever, Monthly logs
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Hatchful
Free logo maker from Shopify.
Free forever, Free logo maker
AI Design
AI Design
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Opik
Open-source LLM evaluation and tracing.
Free forever
Dev Infrastructure & AI APIs
Dev Infrastructure & AI APIs
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Observable
Data apps, notebooks and AI-assisted analysis.
Free forever
Data & Analytics AI
Data & Analytics AI
Free accountTry
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Logseq
Free open-source knowledge base.
Free forever
AI Productivity
AI Productivity
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