OpenAI upgrades ChatGPT and Codex with new GPT-6.1 Terra model

OpenAI released GPT-6.1 Terra, upgrading its medium-sized model from GPT-5.6 and pricing it 50% lower than the version it replaces, with availability today through ChatGPT Work, Codex, and the API. OpenAI said the error rate on its internal benchmark of error-inducing prompts fell from 53.6% at low reasoning effort with GPT-5.6 Terra to 16.7% with GPT-6.1 Terra, a drop of nearly 37 percentage points, and fell 18 percentage points to 4.3% at maximum effort, nearly matching GPT-6 Astra and GPT-6.1 Sol. The release follows OpenAI's September 2026 GPT-6 update that included Sol and Luna but excluded Terra, and OpenAI positions GPT-6.1 Terra for computer-based work such as drafting proposals, interpreting technical drawings, filling out forms, and editing videos.

Earth is so back. Last month when OpenAI released https://9to5mac.com/2026/09/22/openai-upgrading-chatgpt-and-codex-with-two-more-gpt-6-models/ GPT-6 models of Sol and Luna, its medium model Terra was excluded from the update. Now OpenAI has upgraded Terra from GPT-5.6 to GPT-6.1, touting speed and computer use at a lower price. GPT-6.1 Terra is OpenAI’s new medium-sized model that balances intelligence and affordability OpenAI currently has four main model classes, ranging from lowest price and capability to highest: Luna, Terra, Sol, and Astra. Today’s GPT-6.1 Terra model release sounds like a great solution for doing more work for longer without costing as much. Here are the high-level details from the announcement: We’re introducing GPT-6.1 Terra , a fast, efficient model that combines detailed visual reasoning and precise computer use alongside clearer, more natural writing. A significant step up from GPT‑5.6 Terra, it excels at the communication and computer-based tasks that fill the workday, from drafting proposals and interpreting technical drawings to filling out forms and editing videos. OpenAI highlights that GPT-6.1 Terra pricing is actually 50% lower than the inferior version that it replaces, GPT-5.6 Terra, which makes it ideal for automating computer work tasks for less. In terms of intelligence and accuracy, OpenAI says Terra is a step forward in these areas as well: On our internal benchmark of error-inducing prompts, the error rate at low reasoning effort fell from 53.6% with GPT-5.6 Terra to 16.7% with GPT-6.1 Terra, a drop of nearly 37 percentage points. At maximum effort, the error rate fell by 18 percentage points to 4.3%, nearly matching the rates for GPT-6 Astra and GPT-6.1 Sol. The new GPT-6.1 Terra model is available today through ChatGPT Work, Codex, and the API. You can learn much more about the new medium-sized model here https://openai.com/index/introducing-gpt-6-1-terra/ . Do more with your Apple products AirPods 5 | Apple’s newest wireless headphones https://amzn.to/4hnE1jt Apple AirTag 2 | Add Find My tracking to keys, bags, bikes, more https://amzn.to/4vjNWN1 AirPods Pro 3 | Apple’s best wireless headphones https://amzn.to/4ut3FYp FTC: We use income earning auto affiliate links. More. https://9to5mac.com/about/ affiliate our homepage http://9to5mac.com/ for all the latest news, and follow 9to5Mac on exclusive stories https://9to5mac.com/feature/exclusive/ , reviews https://9to5mac.com/guides/review/ , how-tos https://9to5mac.com/guides/how-to/ , and subscribe to our YouTube channel https://www.youtube.com/9to5mac