OpenAI has introduced GPT-4.1, a successor to the GPT-4o multimodal AI model launched by the company last year. During a livestream on Monday, OpenAI said GPT-4.1 has an even larger context window and is better than GPT-4o in “just about every dimension,” with big improvements to coding and instruction following.

GPT-4.1 is now available to developers, along with two smaller model versions. That includes GPT-4.1 Mini, which, like its predecessor, is more affordable for developers to tinker with, and GPT-4.1 Nano, an even more lightweight model that OpenAI says is its “smallest, fastest, and cheapest” one yet.

All three models can process up to one million tokens of context — the text, images, or videos included in a prompt. That’s far more than GPT-4o’s 128,000-token limit. “We trained GPT‑4.1 to reliably attend to information across the full 1 million context length,” OpenAI says in a post announcing the models. “We’ve also trained it to be far more reliable than GPT‑4o at noticing relevant text, and ignoring distractors across long and short context lengths.”

GPT 4.1 is also 26 percent cheaper than GPT-4o, a metric that has become more important following the debut of DeepSeek’s ultra-efficient AI model.

The launch comes as OpenAI plans to phase out its two-year-old GPT-4 model from ChatGPT on April 30th, announcing in a changelog that recent upgrades to GPT‑4o make it a “natural successor” to replace it. OpenAI also plans to deprectate the GPT-4.5 preview in the API on July 14th, as “GPT‑4.1 offers improved or similar performance on many key capabilities at much lower cost and latency. ”

GPT-4o, the current default model in ChatGPT, was updated last month to bring new image-generation capabilities to the chatbot, which proved so popular that OpenAI had to limit requests and put access to free ChatGPT accounts on hold to prevent its GPUs from “melting.”

The GPT-4.1 reveal confirms our report from last week about OpenAI preparing to launch new models, and marks a pivot in the company’s release schedule. On April 4th, CEO Sam Altman announced on X that the GPT-5 launch was being pushed back and should now arrive “in a few months,” later than the May deadline that was previously expected. Altman says that the delay is partly because OpenAI “found it harder than we thought it was going to be to smoothly integrate everything.”

OpenAI is also set to debut the full version of its o3 reasoning model and an o4 mini reasoning model any day now, with references having already been spotted in the latest ChatGPT web release by AI engineer Tibor Blaho.