Claude Haiku 4.5 vs GPT-5.1-Codex
Compare Claude Haiku 4.5 by Anthropic against GPT-5.1-Codex by OpenAI, in 10 community votes, claude haiku 4.5 wins 60% of head-to-head duels, context windows of 200K vs 400K, tested across 53 shared challenges. Updated April 2026.
Which is better, Claude Haiku 4.5 or GPT-5.1-Codex?
Claude Haiku 4.5 is the better choice overall, winning 60% of 10 blind community votes on Rival. Claude Haiku 4.5 costs $1/M input tokens vs $1.25/M for GPT-5.1-Codex. Context windows: 200K vs 400K tokens. Compare their real outputs side by side below.
Key Differences Between Claude Haiku 4.5 and GPT-5.1-Codex
Claude Haiku 4.5 is made by anthropic while GPT-5.1-Codex is from openai. Claude Haiku 4.5 has a 200K token context window compared to GPT-5.1-Codex's 400K. On pricing, Claude Haiku 4.5 costs $1/M input tokens vs $1.25/M for GPT-5.1-Codex. In community voting, In 10 community votes, Claude Haiku 4.5 wins 60% of head-to-head duels.
In 10 community votes, Claude Haiku 4.5 wins 60% of head-to-head duels. Claude Haiku 4.5 leads in Web Design, while GPT-5.1-Codex leads in Reasoning. Based on blind community voting from the Rival open dataset of 10+ human preference judgments for this pair.
Pick Claude Haiku 4.5. In 10 blind votes, Claude Haiku 4.5 wins 60% of the time. That's not luck.
Pick Claude Haiku 4.5 for Web Design. Pick GPT-5.1-Codex for Reasoning.
Style Comparison
Claude Haiku 4.5 uses 20.4x more emoji
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