Claude Sonnet 4.5 vs GPT-5 Codex

Compare Claude Sonnet 4.5 by Anthropic against GPT-5 Codex by OpenAI, in 245 community votes, claude sonnet 4.5 wins 70% of head-to-head duels, tested across 42 shared challenges. Updated February 2026.

In 245 community votes, Claude Sonnet 4.5 wins 70% of head-to-head duels. Claude Sonnet 4.5 leads in Web Design, Reasoning, Image Generation. Based on blind community voting from the RIVAL open dataset of 245+ human preference judgments for this pair.