LangSmith vs Pydantic Logfire
Facts come from each vendor's own pages; download numbers are the headline package of each tool in 2026-W40.
| Fact | LangSmith | Pydantic Logfire |
|---|---|---|
| PyPI downloads, week (rank) | 18,866,051 (#2)langsmith | 3,488,038 (#5)logfire |
| npm downloads, week (rank) | 8,568,634 (#1)langsmith | 31,486 (#16)@pydantic/logfire-node |
| GitHub stars (rank) | 1,069 (#32)langchain-ai/langsmith-sdk | 4,509 (#23)pydantic/logfire |
| PyPI series (12 weeks) | ||
| npm series (12 weeks) | ||
| Categories | Tracing & observability, Evaluation, Prompt management | Tracing & observability, Evaluation, Gateways with observability |
| Status | Generally available | Generally available |
| Licence | Proprietary | Proprietary |
| Self-host | Enterprise only | Enterprise only |
| OpenTelemetry | Native (OTLP) | Native (OTLP) |
| Pricing model | per-seat | usage |
| Entry price | $39/seat/mo; Plus plan per seat per month then pay-as-you-go traces (10k base traces/month included); Developer plan is $0 with 1 seat and 5k base traces | $49/mo; Team plan, 5 seats, 10M records included then $2 per million; Personal plan is free forever (10M records/month, hard-capped); Growth $249/month. |
| Free tier | Yes | Yes |
| Measurability | Measured (mapped SDK packages) | Measured (mapped SDK packages) |
| Sources | pricing · licence · self-host · OTel (checked 2026-10-07) | pricing · licence · self-host · OTel (checked 2026-10-07) |
More downloads means more package installs (including CI and dependencies), not a better product. See the methodology.