CodingFreemium

Helicone

Open-source LLM observability — one-line proxy, full request logs, cost tracking.

Visit Helicone Free 100k requests/mo, Pro $25/mo

What is Helicone?

Helicone is the open-source observability platform for LLM applications. Add one line to your code (point requests through their proxy) and get full request logs, cost tracking, latency monitoring, and caching. Free self-hosted; cheap hosted tier.

Key features

  • One-line proxy integration
  • Full request + response logs
  • Cost tracking per user / per endpoint
  • Prompt caching built-in
  • Open source self-host
  • OpenAI / Anthropic / multi-provider

Pros

  • Easiest LLM observability to set up
  • Open source — self-hostable for free
  • Caching saves serious money at scale

Cons

  • Proxy approach adds tiny latency
  • Eval features less mature than LangSmith
  • UI less polished than competitors

Best for

Indie hackers tracking AI costsStartups shipping AI to productionTeams wanting OSS observabilityAnyone debugging an LLM bill

Alternatives to Helicone

Coding

LangSmith

LLM observability + evals from the LangChain team — production tracing for AI apps.

LLM observability
FreemiumFree 5k traces/mo, Plus $39/mo
Released July 2023
Coding

Vellum

LLM dev platform — prompt versioning, evals, monitoring in one tool.

LLM dev platform
PaidFrom $500/mo
Released July 2023