Starter plan free with $10 credits monthly, 1 GB processed data, 10k scores, 14-day retention. Pro plan $249/month with $100 credits, 5 GB processed data, 50k scores, 30-day retention. Enterprise with custom pricing. Overage charges at $4/GB for Starter and $3/GB for Pro on processed data.
Key features
Hierarchical traces capture every LLM call, tool invocation, and retrieval step
LLM-as-a-judge, heuristic functions, or human review evaluations
Prompt management with one-click deployments and rollbacks
Playground to test prompts on real production inputs and compare models
Experiments with test cases and side-by-side comparison
Human annotation and collaborative human-in-the-loop workflows
Cost and latency monitoring with dashboards and alerts
REST APIs and Query SDK for data access
Langfuse Assistant to automate the AI engineering loop
Real-time trace inspection
LLM scoring and evaluation
Production monitoring dashboards
Automated pattern detection
Dataset versioning and management
Prompt optimization with Loop agent
Natural language trace investigation
Custom annotation interfaces
Gateway API for unified access
Brainstore database for AI data
What makes it different
MIT licensed open source platform with no data lock-in
Enterprise scale architecture handling billions of monthly events
Works with any language and framework with no framework lock-in
Async by default so tracing never blocks your application
Built specifically for agents which fail differently than normal software
Automatic pattern discovery from production data
Framework agnostic with no vendor lock-in
Enterprise security with SOC 2 Type II and HIPAA compliance
Brainstore query engine for faster production debugging