LangSmith vs PostHog
A side-by-side comparison of LangSmith and PostHog, drawn from Ignaite's continuously-verified listings.
Compared from listings verified as of
At a glance
| Attribute | LangSmith | PostHog |
|---|---|---|
| Category (differs) | Observability | Analytics |
| Pricing | FREEMIUM | FREEMIUM |
| License (differs) | Proprietary | Open core |
| Deployment (differs) | Cloud | Hybrid |
| Platforms (differs) | API, Web | Web, API |
| Model support | Model-agnostic | Model-agnostic |
| Vendor (differs) | LangChain | PostHog |
The honest brief
LangSmith
Deepest native LangChain/LangGraph tracing — but cloud-only, where Langfuse lets you self-host the same.
- Native LangChain/LangGraph tracing
- Works standalone via SDKs
- Datasets + eval orchestration
- Prompt playground built in
- Closed source, cloud-only
- Self-host is Enterprise-only
- Best value inside LangChain stack
PostHog
Folds LLM analytics into the same platform as product analytics, replay and flags — one stack instead of a separate AI-observability tool.
- Generous free tier (1M events/mo)
- Open source, self-hostable
- Auto-clusters LLM traces by behavior
- Usage-based pricing scales down
- Product breadth can overwhelm small teams
- Self-hosting supported at hobby scale only
- Lighter agent tracing than dedicated LLM-obs tools