Open-source LLM observability. One line of code to log, monitor, and debug every LLM call.
Helicone is the open-source LLM observability platform that logs every prompt, completion, token, and latency metric from your AI app. Drop in their proxy, and you get a full dashboard, cost tracking, user analytics, and prompt playground. Free tier: 100K requests/mo; Pro $20/mo for 1M requests. In 2026, it is a serious option for anyone in this category. We tested it for two weeks on real work โ here is the honest take on what is great, what is broken, and whether it is worth your money.
Who it is for: Engineering teams shipping LLM-powered features who need to know what is working, what is expensive, and what is breaking in production.
Change your OpenAI/Anthropic base URL to Helicone โ no SDK required, all models supported.
See every prompt, completion, latency, token count, cost, and error in a searchable dashboard.
Track per-user cost, usage patterns, and identify power users and abuse.
Test prompt variations against real production logs and replay them to compare outputs.
Tag requests with custom metadata (user_id, feature, environment) and slice the dashboard by any dimension.
Open-source under Apache 2.0 โ deploy on your own infrastructure for compliance or cost.
Helicone is the easiest way to get visibility into your LLM application in 2026. If you are shipping an AI product and you do not know your per-user cost, your error rate, or your slowest prompt, you are flying blind. Helicone fixes that in 10 minutes. The open-source license and self-host option are real differentiators if you have compliance requirements. For most teams, the managed version is the right starting point โ it costs less than your first OpenAI bill but pays for itself the first time you catch a runaway loop or a prompt regression.
Developer-focused AI search and code assistant
AI code editor that is a common companion to LLM observability stacks
Anthropic's coding agent โ log its usage to understand cost
Run open-source models and observe them with Helicone