kitio.aiDatadog LLM Observability vs Arize AI
A side-by-side look at pricing plans, free tiers, features, pros and cons, updated for 2026. Datadog LLM Observability starts at See pricing page and Arize AI starts at $50/mo. 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 and LLM tracing
- Quality evaluations
- Prompt-injection checks
- Cost and token tracking
- APM correlation
- Arize Phoenix open source
- Agent tracing
- Online evaluations
- Drift monitoring
- Debugging copilot
| Feature | Datadog LLM Observability | Arize AI |
|---|---|---|
| Best for | LLM and agent monitoring inside the Datadog observability platform | AI observability and evaluation, plus the open-source Phoenix |
| Category | Models & APIs | Models & APIs |
| Pricing model | Free trial | Freemium |
| Starting price | See pricing page | $50/mo |
| Free plan | No, 14-day trial | Yes |
| Made by | Datadog | Arize AI |
| Based in | United States | United States |
| Rating | No ratings yet | No ratings yet |
| Key features |
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Pricing compared
Datadog LLM Observability starts at See pricing page and Arize AI starts at $50/mo. Check both pricing pages for current plans.
Free plan
Cheapest paid plan
Top plan
Free trial
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
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
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 Datadog LLM Observability if you want:
- Joins AI and infra monitoring
- Built-in safety checks
- Enterprise-ready
Watch out: expensive at scale.
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.
Datadog LLM Observability vs Arize AI FAQ
What is the difference between Datadog LLM Observability and Arize AI?
Datadog LLM Observability: LLM and agent monitoring inside the Datadog observability platform. Arize AI: AI observability and evaluation, plus the open-source Phoenix. Both are models & apis tools.
Is Datadog LLM Observability or Arize AI cheaper?
Datadog LLM Observability starts at See pricing page and Arize AI starts at $50/mo. Check both pricing pages for current plans.
Do Datadog LLM Observability and Arize AI have free plans?
Datadog LLM Observability: No, 14-day trial. Arize AI: Yes.
Who makes Datadog LLM Observability?
Datadog LLM Observability is made by Datadog, based in United States.
Who makes Arize AI?
Arize AI is made by Arize AI, based in United States.
Which should I choose, Datadog LLM Observability or Arize AI?
Choose Datadog LLM Observability if you value joins ai and infra monitoring and built-in safety checks. Choose Arize AI if you value free open-source phoenix and covers classic ml and llms.