Claude Sonnet 4.5 vs OpenAI Codex Mini

Compare Claude Sonnet 4.5 by Anthropic against OpenAI Codex Mini by OpenAI, in 1 community votes, claude sonnet 4.5 wins 100% of head-to-head duels, context windows of 200K vs 200K, tested across 10 shared challenges. Updated April 2026.

Which is better, Claude Sonnet 4.5 or OpenAI Codex Mini?

Claude Sonnet 4.5 is the better choice overall, winning 100% of 1 blind community votes on Rival. Claude Sonnet 4.5 costs $3/M input tokens vs $1.5/M for OpenAI Codex Mini. Context windows: 200K vs 200K tokens. Compare their real outputs side by side below.

Key Differences Between Claude Sonnet 4.5 and OpenAI Codex Mini

Claude Sonnet 4.5 is made by anthropic while OpenAI Codex Mini is from openai. Claude Sonnet 4.5 has a 200K token context window compared to OpenAI Codex Mini's 200K. On pricing, Claude Sonnet 4.5 costs $3/M input tokens vs $1.5/M for OpenAI Codex Mini. In community voting, In 1 community votes, Claude Sonnet 4.5 wins 100% of head-to-head duels.

In 1 community votes, Claude Sonnet 4.5 wins 100% of head-to-head duels. Based on blind community voting from the Rival open dataset of 1+ human preference judgments for this pair.

Our Verdict
Claude Sonnet 4.5
Claude Sonnet 4.5Winner
OpenAI Codex Mini
OpenAI Codex MiniRunner-up

Pick Claude Sonnet 4.5. In 1 blind votes, Claude Sonnet 4.5 wins 100% of the time. That's not luck.

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Claude Sonnet 4.5OpenAI Codex Mini

279 AI models invented the same fake scientist.

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