LangSmith vs Datadog: Which is Better in 2026?
Choosing between LangSmith and Datadog comes down to understanding what each tool does best. This comparison breaks down the key differences so you can make an informed decision based on your specific needs, not marketing claims.
Short on time? Here's the quick answer
We've tested both tools. Here's who should pick what:
LangSmith
Debug, monitor, and optimize your LLM applications and AI agents with comprehensive observability.
Best for you if:
- • You need AI agents features specifically
- • Debug LLM applications with detailed agent tracing.
- • Monitor key business metrics with live dashboards and alerts.
Datadog
Cloud monitoring, security, and AI investigations for DevOps
Best for you if:
- • You need monitoring features specifically
- • Cloud monitoring and security platform
- • Unified observability across infrastructure
| At a Glance |  LangSmith |  Datadog |
|---|---|---|
Starts at | Free tier + paid plansFree tier available | $15/host/month (annual)Infrastructure Pro |
Best For | AI Agents | Monitoring |
Rating | - | - |
Choose LangSmith or Datadog?
Choose LangSmith if
Debug, monitor, and optimize your LLM applications and AI agents with comprehensive observability.
- Provides deep visibility into non-deterministic LLM behavior
- Helps improve application performance and response quality
- Offers comprehensive monitoring and alerting capabilities
- Your work is AI agents-shaped, not monitoring-shaped
Choose Datadog if
Cloud monitoring, security, and AI investigations for DevOps
- Comprehensive platform
- Great visualizations
- 700+ integrations
- Your work is monitoring-shaped, not AI agents-shaped
| Feature | LangSmith | Datadog |
|---|---|---|
| Pricing Model | Freemium | Freemium |
| User Rating | No ratings yet | ★4.4/5 1,156 reviews |
| Categories | AI AgentsDeveloper Tools | MonitoringLog Management |
In-Depth Analysis
LangSmith
Debug, monitor, and optimize your LLM applications and AI agents with comprehensive observability.
Strengths
- +Provides deep visibility into non-deterministic LLM behavior
- +Helps improve application performance and response quality
- +Offers comprehensive monitoring and alerting capabilities
- +Identifies systemic issues and user needs automatically
- +Flexible integration with various frameworks and OTel
Weaknesses
- -Specific pricing details require visiting a separate page
- -Self-hosting is only available on the enterprise plan
- -Requires some setup (e.g., environment variables) to get started
Key features
Datadog
Cloud monitoring, security, and AI investigations for DevOps
Strengths
- +Comprehensive platform
- +Great visualizations
- +700+ integrations
Weaknesses
- -Complex pricing
- -Can be expensive
Key features
Pricing: LangSmith vs Datadog
| Plan | LangSmith | Datadog |
|---|---|---|
| Tier 1 | N/A | Free Free |
| Tier 2 | N/A | $15 /host/month (annual) Infrastructure Pro |
| Tier 3 | N/A | $23 /host/month (annual) Infrastructure Enterprise |
| Tier 4 | N/A | $31 /host/month (annual, with Infra) APM |
| Tier 5 | N/A | $40 /host/month (annual, with Infra) APM Enterprise |
Pricing verified from each vendor's public pricing page. Compare in detail on LangSmith pricing and Datadog pricing.
Who Should Use What?
On a budget?
Both are freemium. Compare plans on their websites.
Go with: LangSmith
Want the highest-rated option?
Neither has user reviews yet.
Go with: LangSmith
Value user reviews?
Neither has user reviews yet.
Go with: Datadog
3 Questions to Help You Decide
What's your budget?
Both are freemium. Pricing won't help you decide here.
What's your use case?
LangSmith is a AI agents tool. Datadog is in monitoring. Pick the category that matches your needs.
How important are ratings?
Neither has user reviews yet.
Key Takeaways
Datadog
- Free tier available
- Our pick for this comparison
LangSmith
- Better fit for AI agents
The Bottom Line
Datadog is our pick.
Frequently Asked Questions
Is LangSmith or Datadog better?
Datadog is rated in our evaluation. Both are freemium.
What are LangSmith and Datadog used for?
LangSmith: Debug, monitor, and optimize your LLM applications and AI agents with comprehensive observability.. Datadog: Cloud monitoring, security, and AI investigations for DevOps.
What does LangSmith cost vs Datadog?
LangSmith is freemium (free tier + paid plans). Datadog is freemium (free tier + paid plans). Visit their websites for detailed pricing.