# ChatGPT API — GPT-4, o1 and o3 integration

> A single REST interface onto OpenAI models for chat and automation.

- Category: Artificial intelligence
- Free tier: $0.00
- Endpoints: 1
- Updated: 2025-11-26
- Home: https://free-api.bilgisam.com/apis/chatgpt-api

## Overview

One endpoint onto the OpenAI model family, including GPT-4 and the reasoning models, for chatbots, support automation and workflow tools.

It removes the SDK and key-management step for products that only need the call.

## Endpoints

| Method | Path | What it does |
| --- | --- | --- |
| POST | `{\n    \` | Generate Sentiment Analysis |

## Frequently asked questions

### Is ChatGPT API — GPT-4, o1 and o3 integration free?

ChatGPT API — GPT-4, o1 and o3 integration has a Basic plan that costs $0 per month and needs no card. Paid plans exist for higher volume and are listed above.

### How do I get an API key for ChatGPT API — GPT-4, o1 and o3 integration?

Subscribe to the free plan on the marketplace listing. The key appears immediately and works in the browser playground before you write any code.

### How many endpoints does ChatGPT API — GPT-4, o1 and o3 integration have?

ChatGPT API — GPT-4, o1 and o3 integration publishes 1 endpoints. Each one is listed above with its method, path and purpose.