Helicone
✓ Editorially verifiedOpen-source LLM observability — one-line proxy install.
In short
Helicone provides LLM observability by changing your OpenAI base URL, enabling logs, cost tracking, and rate limits without code integration. It is best for developers seeking a simple, low-overhead way to monitor API calls and expenses.
Pick Helicone when you want one-line LLM observability with no integration work.
Skip it when you need deep eval datasets or your workload can't tolerate a proxy hop.
Helicone is open-source LLM observability with a brilliantly simple install — change your OpenAI base URL once, and you get logs, costs, caching, rate limits, and prompt observability for every API call. No SDK changes, no integration work, no instrumentation. Self-host or use Helicone Cloud.
For solo developers and small teams that want to see what's happening in their LLM calls without re-engineering their app, Helicone is the lightest-touch option in the eval/observability category. The free tier (100k requests/mo) is enough for most early-stage projects.
The eval and dataset features are less deep than Braintrust's or LangSmith's. Helicone is observability-first; if you need a serious eval workflow, you'll pair it with one of those tools rather than rely on Helicone alone. The proxy approach also adds a network hop, which a small number of latency-sensitive workloads find unacceptable.
Helicone is the answer to "I want to see what my app is spending and where it's slow" without writing a single line of integration code. For that specific goal it's near-unbeatable.
— The AI Tool Bible editorial team
Pros
- ✅ One-line install
- ✅ Open source
- ✅ Generous free tier
- ✅ Cost tracking is genuinely useful
Cons
- ⚠️ Eval features less deep than Braintrust
- ⚠️ Proxy adds a hop
Use cases
Frequently asked
- How do I install Helicone?
- You install Helicone by changing your OpenAI base URL once. This requires no SDK changes, integration work, or instrumentation.
- What is the pricing structure for Helicone?
- Helicone uses a freemium model with a free tier of 100k requests per month. The Pro plan starts at $25 per month.
- Is Helicone suitable for deep evaluation workflows?
- No, Helicone is observability-first and its eval features are less deep than tools like Braintrust or LangSmith. It is best paired with other tools for serious eval workflows.
- Does Helicone support self-hosting?
- Yes, you can choose to self-host Helicone or use Helicone Cloud.
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