kitio.aiLangSmith vs Arize AI
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. LangSmith has the lower starting price: about $39 a month, against $50 for Arize AI.
At 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
- Arize Phoenix open source
- Agent tracing
- Online evaluations
- Drift monitoring
- Debugging copilot
| Feature | LangSmith | Arize AI |
|---|---|---|
| Best for | Tracing, evaluation and deployment platform for LLM agents | AI observability and evaluation, plus the open-source Phoenix |
| Category | Models & APIs | Models & APIs |
| Pricing model | Freemium | Freemium |
| Starting price | $39/mo | $50/mo |
| Free plan | Yes | Yes |
| Made by | LangChain | Arize AI |
| Based in | United States | United States |
| Rating | No ratings yet | No ratings yet |
| Key features |
|
|
Both offer: Agent tracing.
Pricing compared
LangSmith has the lower starting price: about $39 a month, against $50 for Arize AI.
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
3 plans
AX Free
Free
- 25k spans/month
- 1 GB ingestion/month
- 15 days retention
- Unlimited users
AX Pro
$50/mo
- 50k spans/month
- 10 GB ingestion/month
- 30 days retention
AX Enterprise
Contact sales
- Custom plans
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
Arize AI
- Free open-source Phoenix
- Covers classic ML and LLMs
- Strong enterprise features
- AX costs rise with volume
- Two products can confuse
- Steeper setup than simple tools
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 Arize AI if you want:
- Free open-source Phoenix
- Covers classic ML and LLMs
- Strong enterprise features
Watch out: ax costs rise with volume.
LangSmith vs Arize AI FAQ
What is the difference between LangSmith and Arize AI?
LangSmith: Tracing, evaluation and deployment platform for LLM agents. Arize AI: AI observability and evaluation, plus the open-source Phoenix. Both are models & apis tools.
Is LangSmith or Arize AI cheaper?
LangSmith has the lower starting price: about $39 a month, against $50 for Arize AI.
Do LangSmith and Arize AI have free plans?
LangSmith: Yes. Arize AI: Yes.
Who makes LangSmith?
LangSmith is made by LangChain, based in United States.
Who makes Arize AI?
Arize AI is made by Arize AI, based in United States.
Which should I choose, LangSmith or Arize AI?
Choose LangSmith if you value detailed agent traces and strong langgraph integration. Choose Arize AI if you value free open-source phoenix and covers classic ml and llms.