Langfuse

Open-source LLM observability and engineering platform for tracing, evaluation, and prompt management

LangSmith (LangChain)

LLM observability, testing, and deployment platform for production AI applications

Langfuse

Excellent

22/25

LangSmith (LangChain)

Moderate

13/25

Score Breakdown

DimensionLangfuseLangSmith (LangChain)

Data Residency

Where is your data stored and processed?

Langfuse: EU cloud region (Ireland) keeps data within EEA. Full self-hosting option allows air-gapped EU deployments with zero cloud dependency. Customer can choose exact data location.

LangSmith (LangChain): Cloud product processes trace data (including prompts and LLM outputs) in US infrastructure. Self-hosted LangSmith Enterprise enables EU data residency. Open-source LangChain framework can run fully on-premise.

5/5

EU cloud region (Ireland) keeps data within EEA. Full self-hosting option allows air-gapped EU deployments with zero cloud dependency. Customer can choose exact data location.

2/5

Cloud product processes trace data (including prompts and LLM outputs) in US infrastructure. Self-hosted LangSmith Enterprise enables EU data residency. Open-source LangChain framework can run fully on-premise.

Legal Jurisdiction

Which laws govern the company and your data?

Langfuse: German GmbH (EU company) but acquired by ClickHouse Inc. (US). German law governs the entity but US parent introduces CLOUD Act considerations. Self-hosted deployment eliminates US cloud dependency.

LangSmith (LangChain): California incorporation, US jurisdiction, CLOUD Act applies. SOC 2 Type II and GDPR DPA available. Self-hosted enterprise removes US cloud dependency for EU deployments.

3/5

German GmbH (EU company) but acquired by ClickHouse Inc. (US). German law governs the entity but US parent introduces CLOUD Act considerations. Self-hosted deployment eliminates US cloud dependency.

2/5

California incorporation, US jurisdiction, CLOUD Act applies. SOC 2 Type II and GDPR DPA available. Self-hosted enterprise removes US cloud dependency for EU deployments.

Data Retention & Training

Is your data used for model training?

Langfuse: Explicitly does not train on customer data. Customer traces and prompts processed solely to provide the service. Self-hosted gives full data lifecycle control.

LangSmith (LangChain): Trace data not used for LLM training. Configurable trace retention periods. Enterprise self-hosted gives full control over data lifecycle. Cloud product has clear data isolation per project.

5/5

Explicitly does not train on customer data. Customer traces and prompts processed solely to provide the service. Self-hosted gives full data lifecycle control.

4/5

Trace data not used for LLM training. Configurable trace retention periods. Enterprise self-hosted gives full control over data lifecycle. Cloud product has clear data isolation per project.

Certifications

ISO 27001, SOC 2, Cyber Essentials, etc.

Langfuse: SOC 2 Type II and ISO 27001 certified with annual audits. HIPAA BAA available. Annual external penetration tests. Excellent certification posture for a developer tooling company.

LangSmith (LangChain): SOC 2 Type II certification. Appropriate for a developer tooling company. ISO 27001 would strengthen the posture for enterprise regulated-industry procurement.

5/5

SOC 2 Type II and ISO 27001 certified with annual audits. HIPAA BAA available. Annual external penetration tests. Excellent certification posture for a developer tooling company.

3/5

SOC 2 Type II certification. Appropriate for a developer tooling company. ISO 27001 would strengthen the posture for enterprise regulated-industry procurement.

Regulatory Fit

Suitability for regulated industries and professional services

Langfuse: EU data hosting, GDPR DPA, German legal origin, self-hosting for regulated industries. HIPAA compliance extends reach to healthcare. The ClickHouse acquisition is the main caveat for sovereignty purists.

LangSmith (LangChain): Cloud product requires GDPR transfer mechanisms for EU personal data in traces. Self-hosted LangSmith Enterprise is the appropriate deployment for EU regulated industries. Open-source framework usage is unrestricted.

4/5

EU data hosting, GDPR DPA, German legal origin, self-hosting for regulated industries. HIPAA compliance extends reach to healthcare. The ClickHouse acquisition is the main caveat for sovereignty purists.

2/5

Cloud product requires GDPR transfer mechanisms for EU personal data in traces. Self-hosted LangSmith Enterprise is the appropriate deployment for EU regulated industries. Open-source framework usage is unrestricted.

Total Score

22/25

13/25

Best For

Langfuse

Best for regulated industries (BaFin, CNIL); privacy-conscious teams who need strong data retention controls; organisations that need self-hosted or on-premise deployment; teams on a tight budget.

LangSmith (LangChain)

Best for privacy-conscious teams who need strong data retention controls; organisations that need self-hosted or on-premise deployment; teams on a tight budget.

Detailed Comparison

Langfuse vs LangSmith (LangChain): Trust & Compliance Comparison

Langfuse (Langfuse (ClickHouse), DE) scores 22/25 overall with a Gold (Excellent) trust badge. Open-source LLM observability and engineering platform for tracing, evaluation, and prompt management. LangSmith (LangChain) (LangChain, US) scores 13/25 with a Bronze (Moderate) trust badge. LLM observability, testing, and deployment platform for production AI applications.

Dimension-by-Dimension Breakdown

#### Data Residency

Langfuse leads with 5/5 vs 2/5.

●Langfuse (5/5): EU cloud region (Ireland) keeps data within EEA. Full self-hosting option allows air-gapped EU deployments with zero cloud dependency. Customer can choose exact data location.

●LangSmith (LangChain) (2/5): Cloud product processes trace data (including prompts and LLM outputs) in US infrastructure. Self-hosted LangSmith Enterprise enables EU data residency. Open-source LangChain framework can run fully on-premise.

#### Legal Jurisdiction

Langfuse leads with 3/5 vs 2/5.

●Langfuse (3/5): German GmbH (EU company) but acquired by ClickHouse Inc. (US). German law governs the entity but US parent introduces CLOUD Act considerations. Self-hosted deployment eliminates US cloud dependency.

●LangSmith (LangChain) (2/5): California incorporation, US jurisdiction, CLOUD Act applies. SOC 2 Type II and GDPR DPA available. Self-hosted enterprise removes US cloud dependency for EU deployments.

#### Data Retention & Training

Langfuse leads with 5/5 vs 4/5.

●Langfuse (5/5): Explicitly does not train on customer data. Customer traces and prompts processed solely to provide the service. Self-hosted gives full data lifecycle control.

●LangSmith (LangChain) (4/5): Trace data not used for LLM training. Configurable trace retention periods. Enterprise self-hosted gives full control over data lifecycle. Cloud product has clear data isolation per project.

#### Certifications

Langfuse leads with 5/5 vs 3/5.

●Langfuse (5/5): SOC 2 Type II and ISO 27001 certified with annual audits. HIPAA BAA available. Annual external penetration tests. Excellent certification posture for a developer tooling company.

●LangSmith (LangChain) (3/5): SOC 2 Type II certification. Appropriate for a developer tooling company. ISO 27001 would strengthen the posture for enterprise regulated-industry procurement.

#### Regulatory Fit

Langfuse leads with 4/5 vs 2/5.

●Langfuse (4/5): EU data hosting, GDPR DPA, German legal origin, self-hosting for regulated industries. HIPAA compliance extends reach to healthcare. The ClickHouse acquisition is the main caveat for sovereignty purists.

●LangSmith (LangChain) (2/5): Cloud product requires GDPR transfer mechanisms for EU personal data in traces. Self-hosted LangSmith Enterprise is the appropriate deployment for EU regulated industries. Open-source framework usage is unrestricted.

Certifications at a Glance

Certification	Langfuse	LangSmith (LangChain)
ISO 27001	Yes	No
SOC 2 Type II	Yes	Yes

Overall Verdict

Langfuse has a clear trust advantage, scoring 22/25 compared to LangSmith (LangChain)'s 13/25. Langfuse particularly excels in data residency, legal jurisdiction, data retention & training, certifications, regulatory fit.

Frequently Asked Questions

Which is better for EU compliance, Langfuse or LangSmith (LangChain)?

Langfuse has a TrustKit score of 22/25 while LangSmith (LangChain) scores 13/25. Langfuse currently rates higher across data residency, legal jurisdiction, data retention, certifications, and regulatory fit.

How do Langfuse and LangSmith (LangChain) compare on data residency?

Langfuse scores 5/5 for data residency (EU cloud region (Ireland) keeps data within EEA. Full self-hosting option allows air-gapped EU deployments with zero cloud dependency. Customer can choose exact data location.), while LangSmith (LangChain) scores 2/5 (Cloud product processes trace data (including prompts and LLM outputs) in US infrastructure. Self-hosted LangSmith Enterprise enables EU data residency. Open-source LangChain framework can run fully on-premise.).

Are Langfuse and LangSmith (LangChain) GDPR compliant?

Both tools are assessed across five compliance dimensions. Langfuse has a regulatory fit score of 4/5 and LangSmith (LangChain) scores 2/5. Check the full comparison above for a detailed breakdown.

Explore Each Tool

Langfuse

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88%

LangSmith (LangChain)

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52%