Which AI model excels at reasoning abilities?

As of August 2026, the AI model landscape for reasoning abilities is led by GPT-5.6 Sol (OpenAI), which outperforms competitors on standardized logical deduction benchmarks like GPQA Diamond and ARC-Challenge, with a top score of 57.5. It excels in structured, step-by-step reasoning, particularly when using its Think-High/Think-Max compute modes for complex problems. Claude Mythos Preview (Anthropic) and Claude Opus 5 are close contenders, scoring 56.7 and 56.1 respectively, with strengths in nuanced, creative reasoning and long-context tasks. Gemini 3.5 Pro/Flash (Google) leads in multimodal reasoning and large-context processing, while Grok 4.3 (xAI) focuses on real-time information with low hallucination.

Key reasoning traits across top models include:

• ·Skills: Logical operations (e.g., deductive proofs, multi-step math).
• ·Calibration: Confidence aligns with correctness for self-correction.
• ·Strategy: Chain-of-thought planning.
• ·Abstraction: Higher-level concept reuse.

For specialized use cases:

• ·Mathematical/formal logic: OpenAI o3 (or GPT-5.6 Sol in Think modes).
• ·Nuanced trade-off analysis: Claude Opus 4.6/5 or Mythos.
• ·General multi-step reasoning: GPT-5.4/5.6 Sol.
• ·Factual/current-knowledge tasks: Gemini 2.5/3.5 Pro.

Latency varies by mode (120–400 ms per 1k tokens), with higher accuracy requiring deeper compute (e.g., Think-Max). Open-source options like DeepSeek-V4-Pro offer competitive reasoning at lower cost, though they trail proprietary leaders.