# GPT-5 Pro

> OpenAI's pro-tier reasoning model, designed to give smarter and more precise responses on demanding tasks.

## Key facts

- Model author: OpenAI
- Input: $15.00 per 1M tokens
- Output: $120.00 per 1M tokens
- Context window: 400,000 tokens
- Maximum output: 272,000 tokens
- Input modalities: image, text
- Output modalities: text
- Capabilities: reasoning, structured_output, tools, vision
- Released: 2025-10-06
- Knowledge cutoff: Sep 30, 2024
- Model IDs: `openai/gpt-5-pro`
- Model page: https://www.realrelay.ai/model/openai/gpt-5-pro

## Overview

GPT-5 Pro is a pro-tier reasoning model from OpenAI, designed to produce smarter and more precise responses. It accepts text and image input, returns text, and supports tool calling and structured output. Its 272,000-token output limit leaves room for very long answers in a single response.

It has a 400K-token context window and can generate up to 272,000 output tokens. It accepts text and image input and returns text. Its knowledge cutoff is September 30, 2024, and it was released on October 6, 2025.

## Capabilities

GPT-5 Pro supports reasoning, tool calling, structured output and image input, and returns text output.

OpenAI documents GPT-5 Pro as producing smarter and more precise responses, and its output limit of 272,000 tokens leaves room for very long answers.

## Pricing

GPT-5 Pro costs $15.00 per 1M input tokens and $120.00 per 1M output tokens. GPT-5 Pro is available through RealRelay's OpenAI-compatible API.

## Use cases

Use GPT-5 Pro for analysis where precision matters, such as reviewing long technical documents or contracts and returning structured output that downstream systems can parse; the 400K-token context window holds long inputs.

Its large output limit also fits generating long reports or extensive code in a single response, with tool calling to fetch data along the way.

## Call it

OpenAI-compatible chat completions:

```bash
curl https://www.realrelay.ai/v1/chat/completions \
  -H "Authorization: Bearer $REALRELAY_API_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model": "openai/gpt-5-pro", "messages": [{"role": "user", "content": "Hello"}]}'
```

## FAQ

### What is GPT-5 Pro?

GPT-5 Pro is a pro-tier reasoning model from OpenAI, designed to produce smarter and more precise responses.

### How much does GPT-5 Pro cost?

GPT-5 Pro costs $15.00 per 1M input tokens and $120.00 per 1M output tokens.

### What is the context window of GPT-5 Pro?

GPT-5 Pro has a 400K-token context window and can generate up to 272,000 output tokens.

### What inputs and outputs does GPT-5 Pro support?

GPT-5 Pro accepts text and image input and returns text.

### Does GPT-5 Pro support tool calling?

Yes. GPT-5 Pro supports tool calling, along with reasoning, structured output and image input.

### When was GPT-5 Pro released?

GPT-5 Pro was released on October 6, 2025. Its knowledge cutoff is September 30, 2024.

### How do I call GPT-5 Pro via the API?

Call GPT-5 Pro through RealRelay's OpenAI-compatible API by setting the model name to openai/gpt-5-pro.