# OpenLIT vs Arize Phoenix

> Both are open-source options for LLM tracing and evaluation. OpenLIT is Apache 2.0 and OpenTelemetry-native with Prompt Hub, agent monitoring, Vault, and GPU telemetry in one self-hosted platform. Phoenix centres on OpenInference tracing and eval workflows under Elastic License 2.0.

- HTML: https://openlit.io/compare/openlit-vs-arize-phoenix
- Markdown: https://openlit.io/compare/openlit-vs-arize-phoenix.md

Compare OpenLIT and Arize Phoenix for LLM observability. OpenLIT is Apache 2.0 with a full self-hosted platform (traces, evals, Prompt Hub, GPU). Phoenix is Elastic License 2.0 with strong tracing and eval UX.

## Feature comparison

### Core Architecture

| Feature | OpenLIT | Arize Phoenix |
| --- | --- | --- |
| OpenTelemetry-native | Yes | OpenInference / OTel-friendly tracing |
| Open Source | Apache 2.0 | Elastic License 2.0 |
| Self-hostable | Yes | Yes |
| Cloud-managed option | Coming soon | Yes |
| Vendor-neutral OTLP export | Yes | Via OTel / export paths |

### LLM Monitoring

| Feature | OpenLIT | Arize Phoenix |
| --- | --- | --- |
| Token usage tracking | Yes | Yes |
| Cost per request | Yes | Yes |
| Latency / p95 metrics | Yes | Yes |
| Prompt & response logging | Yes | Yes |
| Broad LLM / framework auto-instrumentation | Yes | Yes |

### Infrastructure Monitoring

| Feature | OpenLIT | Arize Phoenix |
| --- | --- | --- |
| GPU monitoring (NVIDIA + AMD) | Yes | No |
| Vector DB tracing | Yes | Yes |
| Multi-environment tagging | Yes | Yes |

### Developer Tools

| Feature | OpenLIT | Arize Phoenix |
| --- | --- | --- |
| Prompt Hub (versioning) | Yes | Eval / playground oriented |
| Evaluations (LLM-as-a-judge) | Yes | Yes |
| Secrets Vault | Yes | No |
| Fleet Hub (multi-deployment) | Yes | No |
| AI agent monitoring UI | Yes | Via traces |

### Observability Backends

| Feature | OpenLIT | Arize Phoenix |
| --- | --- | --- |
| Grafana / Prometheus export | Yes | Via export / OTel |
| Any OTLP-compatible backend | Yes | Via OTel paths |

## When to choose OpenLIT

- You need Apache 2.0 rather than Elastic License 2.0 for compliance or redistribution
- You want Prompt Hub, Vault, agent monitoring, and GPU metrics in the same self-hosted product as traces
- You want fully OpenTelemetry-native spans you can forward to any OTLP backend
- You prefer one AI engineering platform instead of stitching eval UI + separate ops tooling

## When to choose Arize Phoenix

- You prefer Phoenix’s tracing and evaluation UX and are comfortable with Elastic License 2.0
- Your workflows centre on OpenInference and Phoenix notebooks / eval experiments
- You already use Arize’s broader ML observability ecosystem

## Related

- All comparisons: https://openlit.io/compare.md
- Pricing: https://openlit.io/pricing.md
- Docs: https://docs.openlit.io/latest/openlit/quickstart-ai-observability