GPT-6 Astra vs GPT-6.1 Sol: Which Should You Use?

GPT-6.1 Sol nearly matches GPT-6 Astra on coding and professional work at one-fifth of the price. Pricing, specs, cost examples and when Astra is still worth it.

Last updated: 10 October 2026 · By Jake Hissitt, Founder of Stob.AI.

Prices are OpenAI's standard API list prices.

Short answer: for most production work, GPT-6.1 Sol is now the better buy.

OpenAI says it nearly matches GPT-6 Astra on agentic coding, computer use and professional work at one-fifth of Astra's token price .

Keep Astra for the narrow set of tasks where a wrong answer costs far more than the model bill.

OpenAI released GPT-6.1 Sol on 29 September 2026, one week after GPT-6 Sol.

The token price did not change.

The quality did.

Here is what that means for teams choosing between the two.

(Source: OpenAI announcement , GPT-6.1 Sol model docs .) GPT-6 Astra vs GPT-6.1 Sol at a glance Spec GPT-6 Astra GPT-6.1 Sol Position OpenAI's most intelligent model Near-Astra quality, mid-tier price Input / 1M tokens $10.00 $2.00 Cached input / 1M $1.00 $0.10 Cache write / 1M $12.50 $2.50 Output / 1M tokens $50.00 $10.00 Context window 1,050,000 1,050,000 (922K max input) Max output 128,000 128,000 Long-prompt rule Above 272K input tokens the whole request bills at 2× input/cache and 1.5× output Knowledge cutoff 30 Apr 2026 30 Apr 2026 Reasoning effort Low to max Low, medium (default), high, xhigh, max Inputs Text, image Text, image (no audio or video) What changed from GPT-6 Sol to GPT-6.1 Sol Same token price: $2 input and $10 output per million tokens.

Cached input halved: from $0.20 to $0.10 per million, 95% below fresh input.

Agents that resend the same instructions, tools and documents get much cheaper.