LangSmith vs Langfuse
Facts come from each vendor's own pages; download numbers are the headline package of each tool in 2026-W40.
| Fact | LangSmith | Langfuse |
|---|---|---|
| PyPI downloads, week (rank) | 18,866,051 (#2)langsmith | 6,306,471 (#3)langfuse |
| npm downloads, week (rank) | 8,568,634 (#1)langsmith | 3,268,181 (#2)@langfuse/tracing |
| GitHub stars (rank) | 1,069 (#32)langchain-ai/langsmith-sdk | 35,491 (#2)langfuse/langfuse |
| PyPI series (12 weeks) | ||
| npm series (12 weeks) | ||
| Categories | Tracing & observability, Evaluation, Prompt management | Tracing & observability, Evaluation, Prompt management |
| Status | Generally available | Generally available |
| Licence | Proprietary | MIT (open core) |
| Self-host | Enterprise only | Yes |
| 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 | $29/mo; Core cloud plan, 100k units/month included then $8/100k units; Hobby is free (50k units/month); self-hosting is a separate free option |
| 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.