OpenAI Plans GPT-5.4 With Million-Token Context

OpenAI says it will release GPT-5.4 “sooner than you think,” while already shipping GPT-5.3 Instant, the company announced March 5, 2026. Reports say GPT-5.4 may provide a one million‑token (possibly up to two million) context window and an “extreme” reasoning mode, aimed at deeper research and larger code tasks. The rollout comes amid user backlash over OpenAI’s U.S. defense contract.