Gemini 4 Carbon takes the MathArena crown but costs 15 times more than GPT-6.1 Sol

Nov 14, 2026

Google's Gemini 4 Carbon has become the first non-OpenAI model in a while to top the MathArena math benchmark. It knocked GPT-6.1 Sol from the top spot, while Claude Fable 5.2 came in second, making it potentially one of the most capable publicly available models for math tasks. OpenAI's models, which recently allegedly solved demanding equations like the Navier-Stokes equations, aren't publicly available yet.

Gemini 4 Carbon's most common failure mode is exceeding the time limit. The model also almost never gives up on a task, a trait that can be read as either positive or negative. In one case, it launched a script that ran for more than eleven hours without checking on its progress. That extra performance comes at a price, though. With the reasoning settings used in testing, Carbon and Fable 5.2 cost roughly 15 and 40 times as much as GPT-6.1 Sol, respectively.

Recommendation	Model	Provider	Release date	Expected performance	Expected cost
#1 overall	Gemini 4 Carbon (high)	Google	November 10, 2026	85.4% ±3.0%	$15.70 ±$1.33
#2 overall	Claude-Fable-5.2 (max)	Anthropic	November 9, 2026	82.8% ±5.3%	$40.20 ±$2.59
#3 overall	GPT-6.1 Sol (max)	OpenAI	September 29, 2026	80.6% ±2.7%	$1.07 ±$0.018
Best open model	Kimi K3.1 Pro (max)	Moonshot AI	October 23, 2026	54.3% ±5.8%	$3.70 ±$0.27

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