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OpenAI

AI ModelTrending

GPT models for chat, reasoning and agents

About OpenAI

Access GPT-4o, GPT-5 and o-series reasoning models through a unified chat/responses API. Industry-standard for assistants, RAG and multi-step agents.

Highlights

  • Production-ready with strong developer documentation
  • Transparent paid pricing
  • Trusted by developers building AI-native products
  • Public REST API — try it right here in the browser

FAQ

What is OpenAI?+

Access GPT-4o, GPT-5 and o-series reasoning models through a unified chat/responses API. Industry-standard for assistants, RAG and multi-step agents.

Is OpenAI free to use?+

OpenAI is offered under a paid model. Check the website for the latest tiers.

What are alternatives to OpenAI?+

Popular alternatives include Anthropic Claude, Google Gemini, Mistral AI

Alternatives to OpenAI