OpenAI: GPT Terra Latest

OpenAI: GPT Terra Latest is a rolling API alias that resolves to the newest model in the GPT Terra tier. As of its introduction, that target is GPT-5.6 Terra, the mid-tier member of the GPT-5.6 family launched in July 2026 alongside flagship Sol and budget Luna. Terra is positioned for everyday professional work where teams want strong reasoning, tool use, and multimodal understanding without Sol-level cost. It supports a very large context window (about 1.05M tokens), up to 128K output tokens per response, configurable reasoning effort from none through max, programmatic tool calling, function calling, and native multimodal inputs including text and images.

On OpenAI’s GPT-5.6 evaluation suite, Terra delivers competitive frontier-class results at substantially lower estimated cost than GPT-5.6 Sol. Highlights include 92.9% on GPQA Diamond, 87.4% on Terminal-Bench 2.1, 63.4% on SWE-Bench Pro, 69.6% on DeepSWE, 87.5% on BrowseComp, 50.4% on Agents’ Last Exam, and 80.7–82% on MMMU-Pro depending on tool access. Independent trackers also report strong coding-agent results, including roughly 95% on SWE-bench Verified (Vals AI). Terra is described as outperforming prior GPT-5.5 peak performance on several workloads while using fewer tokens and less latency than larger tiers.

GPT Terra Latest is proprietary and available only through hosted APIs (OpenAI API, ChatGPT Work, Codex, and partner routes such as Azure OpenAI and OpenRouter). Pricing for the underlying Terra snapshot is typically about $2 per million input tokens and $12 per million output tokens, with prompt caching discounts. Parameter count and training compute are not disclosed. Knowledge cutoff for the current Terra generation is February 16, 2026.