OpenAI's GPT-6.1 Terra is on the OpenAI endpoint as of 26 October 2026. CompareLLM read that endpoint on 28 October.
The published list price is $1 input and $5 output per million tokens. Cache reads are $0.05. The context window is 1.05 million tokens and the completion ceiling is 128,000. Median throughput on that route was 58 tokens per second, and median time to first token was 2.75 seconds. Those speed figures are OpenRouter's trailing thirty-minute median for one route, not a CompareLLM measurement.
Where it sits on the current index
Artificial Analysis Intelligence Index v5.0 is a different index from the v4.3 numbers in our September stories. On 28 October the Terra page scores 51. Claude Opus 5.5 scores 58 on the same index, and GPT-6.1 Sol scores 55. Terra is the cheaper of the two OpenAI rows, not the higher score.
The Terra page's title names a Max configuration. The OpenRouter SKU we recorded is openai/gpt-6.1-terra at the $1/$5 rate the same page lists. We did not find a separate v5.0 score for gpt-6.1-terra-pro.
Category ratings on CompareLLM that use this index are labelled estimates. They are an ordering anchor, not a SWE-bench or Arena result. Accepted benchmark results replace them.
What to open next
The pair page against Claude Opus 5.5 is the direct flagship comparison. Sol remains the higher v5.0 score in the GPT-6.1 line, at $2 input and $10 output.
