LangSmith vs OpenTelemetry: Which is Better in 2026?
Choosing between LangSmith and OpenTelemetry? Both are popular llm observability & evals tools. Below we compare them on pricing, free tiers, features, and pros & cons so you can pick the right fit for your stack.
Quick verdict
Both LangSmith and OpenTelemetry are strong llm observability & evals choices. The right pick comes down to your specific feature needs, existing stack, and team preferences.
LangSmith vs OpenTelemetry — Side by Side
| LangSmith | OpenTelemetry | |
|---|---|---|
| Category | LLM Observability & Evals | LLM Observability & Evals |
| Pricing | Free · paid from $39/seat/mo | Free |
| Starting price | Free tier available | Free tier available |
| Free tier | ||
| Rating | 4.5 | 4.6 |
| Best for | LLM Observability & Evals — llm, observability | LLM Observability & Evals — observability, tracing |
Pros & Cons
- Best-in-class visibility into LangGraph and LangChain agents
- Mature evals, datasets and annotation queues
- Accepts OpenTelemetry traces from non-LangChain code
- Per-seat and per-trace pricing both scale with you
- Trace pricing has changed repeatedly, so budgets drift
- Self-hosting requires an Enterprise contract
- No vendor lock-in: switch backends without re-instrumenting
- One trace spans your API, database and model calls
- Every serious observability vendor accepts OTLP
- Apache 2.0 licensed, CNCF governed
- No UI, evals or prompt management of its own
- You still have to pick and pay for (or run) a backend
- GenAI conventions are still evolving, so attribute names can shift
Key Features Compared
LangSmith
- 10,000 base traces / month included
- Pay as you go beyond that
- Unlimited seats
- Extended 180-day retention available
OpenTelemetry
- SDKs for every major language
- OpenTelemetry Collector for routing and sampling
- GenAI semantic conventions for LLM, agent and MCP spans
- Export to any OTLP-compatible backend
Choose LangSmith if…
- You want a free tier to validate before paying.
- Best-in-class visibility into LangGraph and LangChain agents
- Mature evals, datasets and annotation queues
- Accepts OpenTelemetry traces from non-LangChain code
Choose OpenTelemetry if…
- You want a free tier to validate before paying.
- No vendor lock-in: switch backends without re-instrumenting
- One trace spans your API, database and model calls
- Every serious observability vendor accepts OTLP
Frequently Asked Questions
Is LangSmith better than OpenTelemetry?⌄
Both LangSmith and OpenTelemetry are strong llm observability & evals choices. The right pick comes down to your specific feature needs, existing stack, and team preferences.
What is the difference between LangSmith and OpenTelemetry?⌄
LangSmith — LangChain's tracing and evaluation platform, the deepest fit for LangGraph agents. It is priced per seat plus per trace. OpenTelemetry — The vendor-neutral standard for traces, metrics and logs, with GenAI conventions that describe LLM calls, agents and MCP in one shared schema. Both are llm observability & evals tools; the comparison table above breaks down pricing, free tiers, and what each is best for.
LangSmith vs OpenTelemetry: which is cheaper?⌄
LangSmith pricing: Free · paid from $39/seat/mo. OpenTelemetry pricing: Free. Confirm current pricing on each tool's official site, as plans change.
Which is rated higher, LangSmith or OpenTelemetry?⌄
In our catalog, LangSmith rates 4.5 out of 5 and OpenTelemetry rates 4.6 out of 5, so OpenTelemetry has a slight edge on reviews.
See more options in our guide to the best llm observability & evals tools for startups.
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