OpenAI introduced GPT-5.4 across ChatGPT, Codex, and API
OpenAI launched GPT-5.4 on March 5, 2026, with rollout to paid ChatGPT users, all Codex users, and immediate API availability. OpenAI also exposed GPT-5.4 Pro in the API, pricing GPT-5.4 at $2.50 input / $0.25 cached input / $15 output per 1M tokens and GPT-5.4 Pro at $30 input / $180 output per 1M tokens.
Impact Assessment
Sources
OpenAI says GPT-5.4 starts rolling out to paid ChatGPT users today and to all users in Codex.
The GPT-5.4 model page lists a 1,050,000 token context window, 128,000 max output tokens, and $2.50 input / $0.25 cached input / $15 output pricing.
The GPT-5.4 Pro model page lists $30 input / $180 output pricing and the same 1,050,000 token context window.
OpenAI API pricing lists GPT-5.4 and GPT-5.4 Pro token prices and notes higher pricing for prompts above 272K tokens.
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