GPT-6.1 Sol brings near Astra-level reasoning at much lower cost. Most teams pic
By Mattvillage · November 11, 2026 · Curated by George's Blog
GPT-6.1 Sol brings near Astra-level reasoning at much lower cost.
Most teams pick one model and use it for everything.
Then wonder why the bill keeps climbing.
Or why the hard tasks still come back thin.
Honestly, I did exactly that for months.
Now, model choice is a budget line.
Before, I never had to think about it.
So I broke the full Sol guide into one infographic.
Every level, tool and limit, in one place.
What it is: OpenAI's advanced reasoning model, built to land near Astra-level capability at a significantly lower cost.
Best for complex coding, research, data analysis, business strategy, agentic workflows, computer-use agents, large documents and professional deliverables.
The founders who get this early match the model to the task, not the hype.
The specs:
→ 1.05M token context window
→ 128K max output
→ Knowledge cutoff April 30, 2026
→ Text and image input, structured outputs, function calling
→ No fine-tuning
→ $2.00 input, $0.10 cached input, $10.00 output per 1M tokens
Five reasoning levels:
→ Low for fast, simple tasks
→ Medium is the best default
→ High for complex coding
→ Extra High for difficult professional work
→ Max for peak quality
Start at Medium.
Climb only when the task earns it.
Built-in tools: web search, file search, code interpreter, hosted shell, computer use, MCP, image generation, skills, tool search and function calling.
Knowledge stops at the cutoff, so web search closes the gap on anything current.
Which model, when:
→ Luna for speed
→ Sol for complex everyday work
→ Astra for the hardest problems
Prompt it in this order: Role, Goal, Context, Constraints, Input, Output, Process, Quality bar.
Give it real source material.
Define exactly what you want.
Set constraints and the output format.
Use tools for current information.
Ask it to verify key assumptions.
Break big projects into stages.
Where it falls short:
→ It can still hallucinate
→ Higher reasoning does not guarantee correctness
→ Huge contexts add latency and cost
→ No native audio or video input
Fine-tuning is off the table too, so your prompt does the heavy lifting.
So verify anything critical before it ships.
As of October 3, 2026 it's live in ChatGPT Work and Codex for eligible paid plans, and through the API.
Get the free ChatGPT for Work bundle: https://lnkd.in/epRWkJTw
If you build with AI daily, my posts are probably your kind of thing.
Know someone still running one model for everything?
Pass this their way.
Curious which reasoning level you default to, and why.