Skip to content

Fiddler AI vs Helicone

A side-by-side comparison of Fiddler AI and Helicone, two Observability tools, drawn from Ignaite's continuously-verified listings.

Compared from listings verified as of

Fiddler AI

Observability

AI observability and security platform for LLM apps, agents, and ML models.

View Fiddler AI

Helicone

Observability

Drop-in LLM proxy with logging, caching, and cost tracking.

View Helicone

At a glance

Feature comparison of Fiddler AI and Helicone
AttributeFiddler AIHelicone
CategoryObservabilityObservability
Pricing (differs)PAIDFREEMIUM
License (differs)ProprietaryOpen core
Deployment (differs)CloudHybrid
Platforms (differs)Web, APIAPI, Web
Model supportModel-agnosticModel-agnostic
Vendor (differs)Fiddler AIHelicone

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

Helicone

Fastest setup in the category: change one base URL, no SDK, and the open-source proxy can be self-hosted.

  • No SDK or code changes to integrate
  • Open source, self-hostable
  • Built-in caching and rate-limit handling
  • Multi-provider gateway
  • Request/response focused, not span-based
  • Weaker multi-step agent tracing
  • Proxy adds a network hop
  • Lighter eval tooling than Langfuse