GPT-6.1 Terra vs. GPT-6 Astra: One Sacrifices Accuracy for Lower Cost and Higher Speed at High Effort
The New Stack, Friday, October 30th, 2026
A hands-on test of OpenAI's GPT-6.1 Terra versus GPT-6 Astra found Terra far cheaper and faster but less accurate on hard tasks at high effort.
OpenAI released GPT-6.1 Terra on October 26, priced at $1 and $5 per million input and output tokens, a tenth of Astra's $10 and $50.
The author ran three synthetic tests through the API at high reasoning effort, and both models matched on easy and medium tests.
On a 500-row data task Terra took 133 seconds for $0.079, against Astra's 320 seconds for $1.65.
Terra got six answers wrong, four off by one or two, and declined to calculate six totals, while Astra scored 50 of 50 on a rule-checking test to Terra's 45, though these are single-run results.