Fiddler AI vs Langfuse
A side-by-side comparison of Fiddler AI and Langfuse, two Observability tools, drawn from Ignaite's continuously-verified listings.
Compared from listings verified as of
Fiddler AI
ObservabilityAI observability and security platform for LLM apps, agents, and ML models.
View Fiddler AILangfuse
ObservabilityOpen-source LLM observability. Self-hostable, OpenTelemetry-native.
View LangfuseAt a glance
| Attribute | Fiddler AI | Langfuse |
|---|---|---|
| Category | Observability | Observability |
| Pricing (differs) | PAID | FREEMIUM |
| License (differs) | Proprietary | Open core |
| Deployment (differs) | Cloud | Hybrid |
| Platforms (differs) | Web, API | API, Web |
| Model support | Model-agnostic | Model-agnostic |
| Vendor (differs) | Fiddler AI | Langfuse |
| Capabilities (differs) |
|
|
The honest brief
Fiddler AI
Extends a pre-LLM explainable-AI and ML-monitoring platform (founded 2018) to LLM/agent observability and guardrails.
- Covers classic ML and LLM monitoring
- Trust Service scores hallucination, PII, toxicity
- Low-latency guardrails + alerting
- Strong explainability heritage
- Enterprise, sales-quoted pricing
- Heavier to adopt than dev-first tools
- Overkill for small LLM apps
Langfuse
The MIT-licensed, self-hostable answer to LangSmith — own your observability data, framework-agnostic.
- Own your observability data
- Framework-agnostic, OTel-native
- Tracing + evals + prompt mgmt
- Transparent unit-based pricing
- Self-host infra cost at scale
- Less deep LangChain integration
- Setup heavier than hosted-only
When to pick which
Across the signals we compare, Fiddler AI and Langfuse differ on pricing, license, and deployment:
- Pricing
- PAID · FREEMIUM
- License
- Proprietary · Open core
- Deployment
- Cloud · Hybrid
Their capability lists differ in recorded depth — compare the full lists above before deciding.