LangSmith
8.0#1 in llm gateway software$39 usage-basedFree planWebAPILinuxmacOS
VisitLangSmith vs PromptLayer
PromptLayer
7.0#4 in prompting toolFrom $49 a monthFree planWebAPISelf-hosted
VisitWhat both publish
| Fact | LangSmith | PromptLayer |
|---|---|---|
| Evaluation | Evaluation supports offline datasets, online production evaluations, human annotation queues and side-by-side experiment comparison. | Evaluations can be triggered on new prompt versions, through the API, or ad hoc in the UI, and include historical backtests and side-by-side model comparisons. |
| Headquarters | San Francisco, California, United States | PromptLayer says it is located in New York City. |
| Hosting | The pricing page lists Cloud hosting for Developer and Plus, with Cloud, Hybrid, or Self-Hosted options for Enterprise. | Free, Pro, and Team are cloud-hosted in the US; Enterprise offers self-hosting on GCP, AWS, or Azure, EU cloud hosting, or cloud-hosted single tenancy. |
| Integrations | Documented integrations cover OpenAI, Anthropic, Bedrock, Gemini, Mistral, LiteLLM, OpenTelemetry, CrewAI, Vercel AI SDK, PydanticAI, AutoGen and many other frameworks and providers. | The LangChain integration exports traces through OpenTelemetry and supports cost and latency analytics, searchable metadata, and turning traces into evaluation datasets. |
| Observability | Its observability features include agent tracing, cost tracking, online LLM-as-judge and code evaluations, trajectory monitoring, and webhook or PagerDuty alerts. | PromptLayer tracks requests, traces, cost, latency, token usage, scores, and custom metadata, with OpenTelemetry span support. |
LangSmith plans
- DeveloperFree
- Plus$39 a month
- EnterprisePriced on request
PromptLayer plans
- FreeFree
- Pro$49 a month
- Team$500 a month
- EnterprisePriced on request
Pick LangSmith if…
LangSmith suits teams building or operating AI agents that need evaluation, prompt workflows, and observability. It supports both hosted and self-hosted deployment options.
Pick PromptLayer if…
PromptLayer suits engineers and domain experts who need to manage prompts and evaluate AI products together. Its enterprise hosting and access-control options may suit teams with specific deployment or governance needs.