OpenAI: GPT-5.4 API

GPT‑5.4 brings together the best of our recent advances in reasoning, coding, and agentic workflows into a single frontier model. It incorporates the industry-leading coding capabilities of GPT‑5.3‑Codex⁠ while improving how the model works across tools, software environments, and professional tasks involving spreadsheets, presentations, and documents. The result is a model that gets complex real work done accurately, effectively, and efficiently—delivering what you asked for with less back and forth.

Frequently Asked Questions

What is the context window of GPT-5.4?

GPT-5.4 supports a context window of up to 1,050,000 tokens.

Does GPT-5.4 support function calling?

Yes. GPT-5.4 supports tool / function calling.

Does GPT-5.4 support reasoning?

Yes. GPT-5.4 is a reasoning-capable model.

What is the knowledge cutoff of GPT-5.4?

The knowledge cutoff of GPT-5.4 is 2025-08-30.