Arena vs LangSmith
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. Arena is completely free, while LangSmith is freemium.
At a glance
Best for
Category
Pricing model
Starting price
Free plan
Made by
Based in
Rating
Key features
- Blind side-by-side voting
- Text and coding leaderboards
- Image and video arenas
- Free model chat
- Style-controlled rankings
- Agent tracing
- Datasets and evaluators
- Prompt hub
- Agent deployment
- Online monitoring
| Feature | Arena | LangSmith |
|---|---|---|
| Best for | Crowdsourced leaderboard ranking AI models by blind human votes | Tracing, evaluation and deployment platform for LLM agents |
| Category | Models & APIs | Models & APIs |
| Pricing model | Free | Freemium |
| Starting price | Free | $39/mo |
| Free plan | Yes, fully free | Yes |
| Made by | Arena Intelligence | LangChain |
| Based in | United States | United States |
| Rating | No ratings yet | No ratings yet |
| Key features |
|
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Pricing compared
Arena is completely free, while LangSmith is freemium.
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
Arena
- Reflects real human preferences
- Covers many modalities
- Free to use
- Votes favor style over accuracy
- Labs can tune for the arena
- Few domain-specific results
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
Which one should you choose?
Choose Arena if you want:
- Reflects real human preferences
- Covers many modalities
- Free to use
Watch out: votes favor style over accuracy.
Choose LangSmith if you want:
- Detailed agent traces
- Strong LangGraph integration
- Works with any framework
Watch out: per-seat pricing adds up.
Arena vs LangSmith FAQ
What is the difference between Arena and LangSmith?
Arena: Crowdsourced leaderboard ranking AI models by blind human votes. LangSmith: Tracing, evaluation and deployment platform for LLM agents. Both are models & apis tools.
Is Arena or LangSmith cheaper?
Arena is completely free, while LangSmith is freemium.
Do Arena and LangSmith have free plans?
Arena: Yes, fully free. LangSmith: Yes.
Who makes Arena?
Arena is made by Arena Intelligence, based in United States.
Who makes LangSmith?
LangSmith is made by LangChain, based in United States.
Which should I choose, Arena or LangSmith?
Choose Arena if you value reflects real human preferences and covers many modalities. Choose LangSmith if you value detailed agent traces and strong langgraph integration.