kitio.aiLangSmith vs Datadog LLM Observability
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. LangSmith starts at $39/mo and Datadog LLM Observability starts at See pricing page. Check both pricing pages for current plans.
LLM and agent monitoring inside the Datadog observability platform
Free trialAt a glance
Best for
Category
Pricing model
Starting price
Free plan
Made by
Based in
Rating
Key features
- Agent tracing
- Datasets and evaluators
- Prompt hub
- Agent deployment
- Online monitoring
- Agent and LLM tracing
- Quality evaluations
- Prompt-injection checks
- Cost and token tracking
- APM correlation
| Feature | LangSmith | Datadog LLM Observability |
|---|---|---|
| Best for | Tracing, evaluation and deployment platform for LLM agents | LLM and agent monitoring inside the Datadog observability platform |
| Category | Models & APIs | Models & APIs |
| Pricing model | Freemium | Free trial |
| Starting price | $39/mo | See pricing page |
| Free plan | Yes | No, 14-day trial |
| Made by | LangChain | Datadog |
| Based in | United States | United States |
| Rating | No ratings yet | No ratings yet |
| Key features |
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Pricing compared
LangSmith starts at $39/mo and Datadog LLM Observability starts at See pricing page. Check both pricing pages for current plans.
Free plan
Cheapest paid plan
Top plan
Free trial
3 plans
Developer
Free
- 1 seat
- 5k base traces / month, then pay as you go
- Community support
Plus
$39/mo
- Per seat
- 10k base traces / month, then pay as you go
- Access to Deployment and Engine
- Unlimited seats
Enterprise
Custom
- Self-hosted and hybrid deployment
- Custom SSO, ABAC and RBAC
- Support SLA
Prices in USD, checked Oct 28, 2026 or later. Plans change often, so confirm on each tool's site before you buy.
Pros and cons
LangSmith
- Detailed agent traces
- Strong LangGraph integration
- Works with any framework
- Per-seat pricing adds up
- Trace retention costs extra
- Self-hosting is enterprise-only
Datadog LLM Observability
- Joins AI and infra monitoring
- Built-in safety checks
- Enterprise-ready
- Expensive at scale
- Best only if you use Datadog
- Less flexible eval workflows
Which one should you choose?
Choose LangSmith if you want:
- Detailed agent traces
- Strong LangGraph integration
- Works with any framework
Watch out: per-seat pricing adds up.
Choose Datadog LLM Observability if you want:
- Joins AI and infra monitoring
- Built-in safety checks
- Enterprise-ready
Watch out: expensive at scale.
LangSmith vs Datadog LLM Observability FAQ
What is the difference between LangSmith and Datadog LLM Observability?
LangSmith: Tracing, evaluation and deployment platform for LLM agents. Datadog LLM Observability: LLM and agent monitoring inside the Datadog observability platform. Both are models & apis tools.
Is LangSmith or Datadog LLM Observability cheaper?
LangSmith starts at $39/mo and Datadog LLM Observability starts at See pricing page. Check both pricing pages for current plans.
Do LangSmith and Datadog LLM Observability have free plans?
LangSmith: Yes. Datadog LLM Observability: No, 14-day trial.
Who makes LangSmith?
LangSmith is made by LangChain, based in United States.
Who makes Datadog LLM Observability?
Datadog LLM Observability is made by Datadog, based in United States.
Which should I choose, LangSmith or Datadog LLM Observability?
Choose LangSmith if you value detailed agent traces and strong langgraph integration. Choose Datadog LLM Observability if you value joins ai and infra monitoring and built-in safety checks.