OpenAI: gpt-5-mini API

A high-efficiency variant of GPT-5 released in August 2025. It inherits GPT-5's native reasoning architecture but is optimized for speed and cost. Excelling in coding, logical classification, and structured data extraction, it is the most cost-effective "reasoning" small model, succeeding the previous o4-mini.

Frequently Asked Questions

What is the context window of gpt-5-mini?

gpt-5-mini supports a context window of up to 400,000 tokens.

Does gpt-5-mini support function calling?

Yes. gpt-5-mini supports tool / function calling.

Does gpt-5-mini support reasoning?

Yes. gpt-5-mini is a reasoning-capable model.

What is the knowledge cutoff of gpt-5-mini?

The knowledge cutoff of gpt-5-mini is 2024-05-30.