Claude 3.5 Sonnet vs Grok 4

Claude 3.5 Sonnet (Anthropic) and Grok 4 (xAI) are both frontier AI models. Claude 3.5 Sonnet was published in June 2024 and Grok 4 in July 2025.

Grok 4 was trained on 5×10²⁶ FLOP, about 18.5x the compute of Claude 3.5 Sonnet at 2.7×10²⁵ FLOP. Training compute is the closest available proxy for how much was invested in a model, though it says nothing on its own about how well that compute was spent.

Grok 4 wins the single benchmark both were scored on. Benchmark counts are a crude scoreboard — the evaluations differ wildly in what they measure and in how saturated they are — so the per-benchmark table below matters more than the tally.