kitio.aiArena vs Langfuse
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. Arena is completely free, while Langfuse 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
- LLM tracing
- OpenTelemetry support
- Prompt management
- Evaluations and datasets
- Self-hosting
| Feature | Arena | Langfuse |
|---|---|---|
| Best for | Crowdsourced leaderboard ranking AI models by blind human votes | Open-source LLM observability, prompt management and evals |
| Category | Models & APIs | Models & APIs |
| Pricing model | Free | Freemium |
| Starting price | Free | $29/mo |
| Free plan | Yes, fully free | Yes |
| Made by | Arena Intelligence | ClickHouse |
| 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 Langfuse is freemium.
Free plan
Cheapest paid plan
Top plan
Free trial
4 plans
Hobby
Free
- Free cloud plan
- Limited usage and history
Core
$29/mo
- 100k units included, $8/100k extra
- 90 days data access
- Unlimited users
Pro
$199/mo
- 3 years data access
- High rate limits
- SOC2 and ISO27001 reports
Enterprise
$2499/mo
- Audit logs and SCIM API
- Uptime and support SLA
- Named support engineer
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
Langfuse
- Free to self-host
- No seat-based fees
- Works with any framework
- Self-hosting needs ops work
- Advanced features on paid tiers
- UI can feel dense
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 Langfuse if you want:
- Free to self-host
- No seat-based fees
- Works with any framework
Watch out: self-hosting needs ops work.
Arena vs Langfuse FAQ
What is the difference between Arena and Langfuse?
Arena: Crowdsourced leaderboard ranking AI models by blind human votes. Langfuse: Open-source LLM observability, prompt management and evals. Both are models & apis tools.
Is Arena or Langfuse cheaper?
Arena is completely free, while Langfuse is freemium.
Do Arena and Langfuse have free plans?
Arena: Yes, fully free. Langfuse: Yes.
Who makes Arena?
Arena is made by Arena Intelligence, based in United States.
Who makes Langfuse?
Langfuse is made by ClickHouse, based in United States.
Which should I choose, Arena or Langfuse?
Choose Arena if you value reflects real human preferences and covers many modalities. Choose Langfuse if you value free to self-host and no seat-based fees.