GPT-5.3-Codex vs Kimi K2.5
Compare GPT-5.3-Codex by OpenAI against Kimi K2.5 by Moonshot AI, in 3 community votes, kimi k2.5 wins 67% of head-to-head duels, context windows of 400K vs 262K, tested across 53 shared challenges. Updated April 2026.
Which is better, GPT-5.3-Codex or Kimi K2.5?
Kimi K2.5 is the better choice overall, winning 67% of 3 blind community votes on Rival. GPT-5.3-Codex costs $1.75/M input tokens vs $0.6/M for Kimi K2.5. Context windows: 400K vs 262K tokens. Compare their real outputs side by side below.
Key Differences Between GPT-5.3-Codex and Kimi K2.5
GPT-5.3-Codex is made by openai while Kimi K2.5 is from moonshotai. GPT-5.3-Codex has a 400K token context window compared to Kimi K2.5's 262K. On pricing, GPT-5.3-Codex costs $1.75/M input tokens vs $0.6/M for Kimi K2.5. In community voting, In 3 community votes, Kimi K2.5 wins 67% of head-to-head duels.
In 3 community votes, Kimi K2.5 wins 67% of head-to-head duels. Kimi K2.5 has the edge overall, but performance varies by task type. Based on blind community voting from the Rival open dataset of 3+ human preference judgments for this pair.
Pick Kimi K2.5. In 3 blind votes, Kimi K2.5 wins 67% of the time. That's not luck.
Kimi K2.5 is 4.7x cheaper per token — worth considering if cost matters.
Style Comparison
GPT-5.3-Codex uses 15.8x more emoji
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