Compare · updated 2026-11-01

GPT-6.1 Sol vs GPT-5.5

GPT-6.1 Sol is better at coding, reasoning; GPT-5.5 is better at quick answers, writing, maths, structured data, long documents, translation. GPT-6.1 Sol is the cheaper of the two on output.

Measured quality by task

TaskGPT-6.1 SolGPT-5.5Better
Quick answers91/10093/100GPT-5.5
Writing93/10094/100GPT-5.5
Coding93/10091/100GPT-6.1 Sol
Reasoning82/10079/100GPT-6.1 Sol
Maths79/10082/100GPT-5.5
Structured data91/10096/100GPT-5.5
Long documents91/10093/100GPT-5.5
Translation89/10092/100GPT-5.5

Quality is Nivana’s measured score for each kind of task, from weekly pairwise evals judged by models from several labs. Prices are live AI Gateway list prices per million tokens. Updated 2026-11-01. How this is measured.

Price and context

GPT-6.1 SolGPT-5.5
LabOpenAIOpenAI
Input per 1M tokens$2$5
Output per 1M tokens$10$30
Typical chat answer$0.010$0.029
Context window1.05M1M
Router picks it forFallback onlyFallback only

Which should you use?

Use the one that wins the kind of work you do most, unless the price gap outweighs the quality gap for easy requests. Or don’t choose: Nivana scores both, and the rest of the pool, on every request and sends it to whichever is best for that request.

Questions

Is GPT-6.1 Sol better than GPT-5.5?

On Nivana’s weekly evals GPT-6.1 Sol scores higher on 2 of 8 task types (coding, reasoning) and GPT-5.5 on 6 (quick answers, writing, maths, structured data, long documents, translation). Neither is better at everything.

Which is better for coding, GPT-6.1 Sol or GPT-5.5?

GPT-6.1 Sol: 93/100 against 91/100 for GPT-5.5 on Nivana’s coding evals.

Which is better for writing, GPT-6.1 Sol or GPT-5.5?

GPT-5.5: 94/100 against 93/100 for GPT-6.1 Sol on Nivana’s writing evals.

Which is cheaper, GPT-6.1 Sol or GPT-5.5?

GPT-6.1 Sol: $10 per million output tokens against $30 for GPT-5.5, about 3.0× less. A typical chat answer costs about $0.010 on GPT-6.1 Sol and $0.029 on GPT-5.5.

Or let the router pick, per request

Nivana sends every message to the model that scores best for it, sets how hard it thinks, and tells you which one answered. 2,000 free credits to start, no card.