Arize Phoenix vs Helicone: LLM observability platforms
Quick Comparison
| Arize Phoenix | Helicone | |
|---|---|---|
| Best For | Teams needing full-stack observability, model performance metrics, and OTel integration. | High-QPS LLM API teams needing low-latency proxy to capture prompts, responses, and usage metrics. |
| Pricing | Free tier available | Free tier available |
| Winner | Our Pick |
Tool Breakdown
Arize Phoenix
Best for most teams needing end-to-end observability and model metrics via OTel-native stack.
- OTel-native integration for traces, metrics, and logs
- Rich model-level metrics and visualization for drift, errors, and performance
- Designed for production monitoring and alerting across deployments
- Not optimized as lightweight gateway for extremely high QPS capture
- Requires OTel pipeline and storage setup (infra work)
Helicone
Open-source LLM observability gateway built for high-throughput request capture and lightweight telemetry export.
- High-throughput gateway designed to handle lots of LLM requests
- Low-latency request capture and request-level telemetry
- Easy to drop in front of LLM APIs to log prompts/responses
- Limited built-in model-level analytics and visualizations
- Needs external observability system (e.g., Arize or Grafana) for deep analysis
Frequently Asked Questions
Which tool is better for production model monitoring? +
Arize Phoenix is better for production model monitoring because it provides OTel-native traces, model metrics, drift detection, and alerting; use Helicone only if you need extreme gateway throughput first.
Can I run Helicone as gateway and send data to Arize Phoenix? +
Yes — use Helicone to capture high-QPS requests and forward telemetry/logs to Arize Phoenix (or another OTel consumer) for model metrics and deeper analysis.
How hard and costly to switch between them? +
Both are open-source so switching low-cost technically, but Arize needs OTel pipeline and storage setup while Helicone is lightweight to deploy; hosted tiers may incur costs as volume grows.