September 28, 2026
GPT-6 Astra speeds up long tasks: Basis's 50-tab workbook completed in half the time
On Sep 28, GPT-6 Astra completed Basis’s 50-tab tax workbook in half the time of GPT-5.6 Sol. Basis also scored about 20% higher in internal evaluations. The API costs $10 per 1 million input tokens and $50 per 1 million output tokens.
Previously, GPT-5.6 Sol handled complex workbooks in Basis. Now GPT-6 Astra completed the same task twice as fast while following templates more closely, consulting primary sources on tax questions, and checking its own work.
The price of speed. GPT-5.6 Sol costs $4 per 1 million input tokens and $20 per 1 million output tokens. Astra costs 2.5 times more, but both models have a 1.05 million-token context window and can produce up to 128,000 tokens per response. In the Responses API, Astra is called as `gpt-6-astra`, and the reasoning level must be selected from `low` to `max`.
In Fast mode, Astra promises up to 2× the speed of Standard at 2× the price.
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