# o3 Pro

The maximum-compute variant of the o3 reasoning family, built for the hardest problems where the deepest possible chain-of-thought deliberation produces meaningfully better results.

- **Model ID:** `openai/o3-pro`
- **Type:** chat
- **Providers:** openai
- **Context window:** 200,000
- **Maximum output tokens:** 100,000
- **Pricing:** $20/1M input tokens, $80/1M output tokens
- **Canonical page:** https://vercel.com/ai-gateway/models/o3-pro

## Supported parameters

Detailed capability metadata has not been reported for this model.

## Example

```ts
import { streamText } from 'ai'

const result = streamText({
  model: 'openai/o3-pro',
  prompt: 'Why is the sky blue?'
})
```

## About

o3 Pro was released on June 10, 2025 as the premium tier of the o3 reasoning model family. It applies maximum compute to each reasoning request, enabling the deepest chain-of-thought analysis available from OpenAI.

The additional compute produces more thorough deliberation: the model explores more solution paths, checks its work more exhaustively, and arrives at conclusions with higher confidence. On the hardest mathematical, scientific, and analytical problems, this translates to measurably better accuracy.

The tradeoff is cost and latency. o3 Pro is the most expensive model in the o3 family and takes the longest to respond. For problems where the difference between good and best matters, that investment is justified. For standard reasoning tasks, o3 or o3-mini provide sufficient quality at substantially lower cost.

## What to consider

o3 Pro applies the most compute per request of any o3 variant. Use it when the problem genuinely requires exhaustive deliberation and the quality difference is consequential.

Most teams reserve o3 Pro for their hardest queries, routing standard reasoning traffic to o3 or o3-mini.

## When to use

### Best For

- **Frontier mathematical reasoning:** The hardest proofs, competition problems, and mathematical research
- **Critical scientific analysis:** Complex derivations and multi-step scientific reasoning where errors have consequences
- **Exhaustive code analysis:** Security audits and algorithmic verification requiring thorough deliberation
- **Research-grade reasoning:** Academic and research problems that benefit from the deepest available analysis
- **High-stakes analytical decisions:** Analyses where maximum reasoning depth directly impacts outcomes

### Consider Alternatives When

- **Standard reasoning:** o3 for most reasoning tasks at lower cost
- **Budget-friendly reasoning:** o3-mini for cost-efficient chain-of-thought on routine problems
- **General-purpose tasks:** GPT-5.2 pro for tasks that need premium quality but not specialized reasoning
- **Fast responses:** Any standard model when response time matters more than reasoning depth

## Best for

- **Frontier mathematical reasoning:** The hardest proofs, competition problems, and mathematical research
- **Critical scientific analysis:** Complex derivations and multi-step scientific reasoning where errors have consequences
- **Exhaustive code analysis:** Security audits and algorithmic verification requiring thorough deliberation
- **Research-grade reasoning:** Academic and research problems that benefit from the deepest available analysis
- **High-stakes analytical decisions:** Analyses where maximum reasoning depth directly impacts outcomes

## Consider alternatives

- **Standard reasoning:** o3 for most reasoning tasks at lower cost
- **Budget-friendly reasoning:** o3-mini for cost-efficient chain-of-thought on routine problems
- **General-purpose tasks:** GPT-5.2 pro for tasks that need premium quality but not specialized reasoning
- **Fast responses:** Any standard model when response time matters more than reasoning depth

## Frequently asked questions

### How does o3 Pro differ from standard o3?

It applies more compute per request, enabling deeper and more exhaustive chain-of-thought reasoning. The improvement is most significant on the hardest problems.

### When is the premium cost justified?

For frontier mathematical proofs, critical scientific analysis, security audits, and other problems where the deepest possible reasoning produces meaningfully better outcomes.

### What context window does o3 Pro support?

200K tokens, matching the o3 family.

### Is o3 Pro slower than o3?

Yes. The additional reasoning compute increases response time. Reserve it for problems where depth justifies the wait.

### How does AI Gateway handle authentication for o3 Pro?

AI Gateway accepts a single API key or OIDC token for all requests. You don't embed OpenAI credentials in your application; AI Gateway routes and authenticates on your behalf.

### What are typical latency characteristics?

This page shows live throughput and time-to-first-token metrics measured across real AI Gateway traffic.

## Links

- [Model page](https://vercel.com/ai-gateway/models/o3-pro)
- [AI Gateway documentation](https://vercel.com/docs/ai-gateway)
- [Provider model documentation](https://platform.openai.com/docs/models/o3-pro)
- [Provider pricing](https://platform.openai.com/docs/pricing)