ChatGPT 6 Sol ⌄

Ask ChatGPT 6 Sol

OpenAI's GPT-6 model for demanding work at lower cost.

Project breakdown Steps, then start

Fact check Flag what is unverified

Honest code status What works, what does not

Workflow automation Mapped end to end

About ChatGPT 6 Sol — examples and limitations

GPT-6 Sol brings the training behind GPT-6 Astra to a cheaper, faster tier. Released September 22, 2026, it makes about half the factual errors of GPT-5.6 Sol (4.5% vs 8.4% on OpenAI's test), though it slips behind its predecessor on DeepSWE repository fixes.

ChatGPT 6 Sol at a glance

Provider	OpenAI
Access on AskAI.free	Premium model; the 7-day Pro trial unlocks access.
Best first test	Difficult everyday work where Astra's allowance weight is hard to justify
Model position	New model in the OpenAI family.

What makes ChatGPT 6 Sol different

GPT-6 Sol is the value point of the GPT-6 family: most of Astra's training advances at a fraction of the allowance weight. Its clearest gains over GPT-5.6 Sol are factual accuracy and honest reporting of coding results rather than raw repository fixing, where the older Sol still scores higher. Make it the default for hard work and escalate to Astra only when it stalls.

What ChatGPT 6 Sol is best for

Difficult everyday work where Astra's allowance weight is hard to justify
Agentic, multi-step tasks - 56.4% on Agents' Last Exam against GPT-5.6 Sol's 53.6%
Business automation flows (33.2% on AutomationBench vs GPT-5.6 Sol's 28.8%)
Answers you need to be right: 4.5% of replies with any factual error, vs 8.4% for GPT-5.6 Sol
Coding help you can trust to report results honestly - deceptive coding behaviour fell to 1.3% from GPT-5.6 Sol's 10.4%

How to use ChatGPT 6 Sol

Step 1 Start difficult work here rather than on Astra. Sol sits a few points below Astra on most published tests, at a quarter of the allowance weight.

Step 2 For repository-level bug fixing, run the same task on GPT-5.6 Sol as well: on DeepSWE the older model scored higher (72.7% vs 68.8%).

Step 3 Ask Sol to check its own claims. Its factual error rate is roughly half of GPT-5.6 Sol's, and an explicit request to verify figures makes the most of that.

Example prompts

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Frequently asked questions

What is GPT-6 Sol?

OpenAI launched Sol on September 22, 2026 as the middle tier of GPT-6. It was trained with methods similar to GPT-6 Astra and positions it for difficult work at lower cost and higher usage limits. Astra remains the top model, and Luna is the high-volume tier below Sol.

Is GPT-6 Sol better than GPT-5.6 Sol?

Mostly, but not everywhere. It leads on Agents' Last Exam (56.4% vs 53.6%), AutomationBench (33.2% vs 28.8%) and factual accuracy. It trails on DeepSWE repository bug fixing (68.8% vs 72.7%) and OSWorld computer use (64.4% vs 66.2%), so for whole-repo coding it is worth trying both.

How far behind Astra is it?

Astra is ahead on every benchmark OpenAI published for both - 59.3% vs 56.4% on Agents' Last Exam, 74.1% vs 68.8% on DeepSWE. Sol runs on a quarter of Astra's allowance weight here, which makes it the better default and Astra the escalation.

Can I use GPT-6 Sol in ChatGPT?

At launch OpenAI offered Sol only in ChatGPT's Work and Codex modes and said it was not yet available in Chat. On AskAI.free it is an ordinary chat model you can talk to directly on a Pro plan.

What does Sol know about recent events?

Its training data stops at April 20, 2026. For anything since, use a Perplexity search model and paste the sources back into Sol.

Is there a free way to try Sol?

Sol is a Pro model. Your first week on the Pro trial is free, so you can test Sol on real work before paying anything.

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