GPT-4.1: Three new million token input models from OpenAI, including their cheapest model yet

April 14, 2025 · Simon Willison

URL: https://simonwillison.net/2025/Apr/14/gpt-4-1/

“These are API-only models right now, not available through the ChatGPT interface (though you can try them out in OpenAI’s API playground).”

OpenAI shipped three GPT-4.1 models with million-token context, API only. Nano undercuts GPT-4o-mini but not Google’s or Amazon’s cheapest models. GPT-4.5, released in February, gets switched off in July. Google had a million-token context for a year before this.