Claude Haiku 4.5 vs OpenAI Codex Mini

Compare Claude Haiku 4.5 by Anthropic against OpenAI Codex Mini by OpenAI, in 3 community votes, claude haiku 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 Haiku 4.5 or OpenAI Codex Mini?

Claude Haiku 4.5 is the better choice overall, winning 100% of 3 blind community votes on Rival. Claude Haiku 4.5 costs $1/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 Haiku 4.5 and OpenAI Codex Mini

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

In 3 community votes, Claude Haiku 4.5 wins 100% of head-to-head duels. Based on blind community voting from the Rival open dataset of 3+ human preference judgments for this pair.

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

Pick Claude Haiku 4.5. In 3 blind votes, Claude Haiku 4.5 wins 100% of the time. That's not luck.

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Claude Haiku 4.5OpenAI Codex Mini

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