Langfuse vs LangSmith

Langfuse and LangSmith both keep prompt history next to traces, but they differ on who runs the software and how the bill is counted. Langfuse is MIT-licensed outside its enterprise folders, can be self-hosted, and meters usage in units. LangSmith charges per seat, from 39 USD on Plus, and offers self-hosting only as an Enterprise add-on. Langfuse GmbH is based in Berlin and joined ClickHouse in January 2026, while LangChain Inc. is a Delaware corporation headquartered in San Francisco. Teams outside the LangChain ecosystem will find Langfuse's open code easier to evaluate.

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Both are reviewed in full in our prompt management software ranking: Langfuse and LangSmith.

1. 01

   Open code, or a sales-issued licence key

   Langfuse's repository puts everything outside the ee directories under the MIT Expat licence, with copyright held by ClickHouse, Inc., and some add-on features need a licence key. Self-hosting runs on Docker Compose, Kubernetes with Helm, or Terraform for AWS, GCP and Azure. LangSmith self-hosting is an add-on to the Enterprise plan, needs a licence key from sales, runs on Kubernetes with ClickHouse, PostgreSQL and Redis, and keeps data in your VPC. Anyone wanting to inspect or run the code without a contract will favour Langfuse.

   Edge: Langfuse

2. 02

   Seats on one side, units on the other

   LangSmith Developer costs 0 USD for one seat with 5k base traces a month. Plus is 39 USD per seat per month with 10k base traces and unlimited seats, and extra usage is pay-as-you-go. Langfuse Hobby is free with 50k units a month and two users, Core is 29 USD, Pro 199 USD and Enterprise 2,499 USD per month, with extra units at 8 USD per 100k. Agents that emit many observations per request will multiply Langfuse's unit count.

   Depends on the buyer

3. 03

   Labels and commits for a prompt

   Langfuse stores prompts with versioning, labels and configuration, links them to traces, and caches them client-side in the SDK so retrieval adds no latency. LangSmith versions prompts through commits and tags, and its playground tests several prompts side by side and over a dataset. Both give you history and a way to point production at a chosen version, so the difference is vocabulary more than capability. On the pages we read, neither tool clearly beats the other for managing prompt text.

   Depends on the buyer

4. 04

   How long the data stays

   On Langfuse cloud, data access grows by plan: 30 days on Hobby, 90 days on Core and three years on Pro. LangSmith lists base trace retention of 14 days, and usage beyond the base allowance is billed in units worth one dollar each. LangSmith's page lists no longer retention option. If you need to look back over a quarter of traces to debug a regression in a prompt, Langfuse's published tiers answer that more clearly than LangSmith's page does.

   Edge: Langfuse

5. 05

   Single sign-on and audit trail

   On Langfuse, SSO sits behind a monthly add-on on the Pro plan, while audit logs and SCIM start at Enterprise. That is a clear ladder, though it means a growing team pays extra for access control. LangSmith lists a custom Enterprise plan with self-hosted and hybrid deployment, and its page gives no starting point for SSO or audit logs. Langfuse is more specific, but its specifics are not cheap, so we leave this round as a tie rather than call a winner.

   Depends on the buyer

6. 06

   Berlin GmbH or Delaware corporation

   Langfuse GmbH has its imprint in Berlin, Germany, and the About page says that in January 2026 it joined ClickHouse, with offices in Berlin, San Francisco, Amsterdam and New York. LangSmith comes from LangChain Inc., a Delaware corporation under Delaware law, headquartered in San Francisco with offices in New York, Boston and Amsterdam. Both have a European office, but only Langfuse registers a German legal entity, so Langfuse is the closer fit for someone wanting a European contracting party.

   Edge: Langfuse

Which of the two runs on hardware I control without a sales call?

Langfuse. Its core is MIT-licensed outside the ee directories and the docs cover Docker Compose, Kubernetes and Terraform. Some add-on features still need a licence key, and LangSmith self-hosting needs an Enterprise add-on.

Why can the Langfuse bill grow faster than the plan price suggests?

Cost follows units of usage, with extra units at 8 USD per 100k. An agent that produces many observations per request multiplies the count. The Hobby plan includes 50k units a month.

Is LangSmith free for a whole team?

No. The Developer plan is 0 USD but covers one seat and 5k base traces a month. Plus is 39 USD per seat per month with unlimited seats.

• Langfuse pricing page: monthly tiers from Hobby to Enterprise, 50k free units, 30-day Hobby access and 8 USD per extra 100k units.
• Langfuse about page: January 2026 move to ClickHouse and the four office locations.
• Langfuse imprint: Langfuse GmbH registered in Berlin.
• Langfuse repository licence: MIT Expat outside ee directories and ClickHouse copyright.
• Langfuse prompt management docs: versions, labels, client-side caching and trace links.
• Langfuse self-hosting docs: Docker Compose, Helm and Terraform routes and licence-key add-ons.
• LangChain pricing page: Developer and Plus seat prices, base traces, 14-day retention and unit value.
• LangSmith prompt concepts: commits, tags and dataset playground testing.
• LangSmith self-hosted docs: Enterprise add-on, sales licence key and Kubernetes stack.
• LangChain about page: San Francisco headquarters and three other offices.
• LangChain terms of service: Delaware corporation and governing law.