Best Reasoning AI Models in 2026
Claude Opus 5.5 leads reasoning AI models on the October 2026 ranking with a score of 86.6, ahead of GPT-6.1 Sol (84.1) and GPT-6 Astra (84). Each row uses the public BenchAlign v5.8 contract and shows its evidence status.
Bottom line: Reasoning models (chain-of-thought) dominate the top of the leaderboard, but they cost more and are slower. Choose reasoning when accuracy matters more than speed.
Full Rankings (150 ranked)
How to choose
Key Takeaways
The top model is Claude Opus 5.5 by Anthropic with a BenchAlign v5.8 score of 86.6 and Supported evidence.
The best open-weight model is MiMo-V2.6-Pro at position #12.
150 models are included in this ranking.
Score in Context
What these scores mean
Reasoning models use chain-of-thought to improve accuracy on complex tasks. They are ranked by the same overall BenchLM score.
Known limitations
Reasoning models are slower and more expensive per token due to longer output chains. The speed/cost trade-off is not reflected in benchmark scores. For latency-sensitive applications, compare with non-reasoning models.
About this ranking
Ranking data as of October 19, 2026
Top AI models with dedicated reasoning capabilities, ranked by benchmark performance.
Unless noted otherwise, ranking surfaces on this page use BenchLM’s provisional leaderboard lane rather than the stricter sourced-only verified leaderboard.
Claude Opus 5.5 leads this ranking with a score of 86.6, followed by GPT-6.1 Sol (84.1) and GPT-6 Astra (84). The top three are separated by just a few points — any of them would perform well for this use case.
The best open-weight option is MiMo-V2.6-Pro (ranked #12 with a score of 73.6). Proprietary models hold a clear advantage in this category, though open-weight options may suffice for less demanding use cases.
This ranking uses provisional overall weighted scores from the active scoring formula. For detailed model profiles, click any model name above. To compare two specific models head-to-head, use the "vs #" links.
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