OpenAI: GPT-5.6 Luna API
GPT-5.6 Luna is designed for cost-sensitive, high-volume workloads. It roughly corresponds to the nano model tier used in earlier GPT-5 families.
- Context window: 1,050,000 tokens
- Max output: 128,000 tokens
- Input: text, image
- Output: text
- Reasoning: Supported
- Tool calling: Supported
- File input: Supported
- Released: 2026-07-08
- Knowledge cutoff: 2026-02-15
Frequently Asked Questions
What is the context window of GPT-5.6 Luna?
GPT-5.6 Luna supports a context window of up to 1,050,000 tokens.
Does GPT-5.6 Luna support function calling?
Yes. GPT-5.6 Luna supports tool / function calling.
Does GPT-5.6 Luna support reasoning?
Yes. GPT-5.6 Luna is a reasoning-capable model.
What is the knowledge cutoff of GPT-5.6 Luna?
The knowledge cutoff of GPT-5.6 Luna is 2026-02-15.