GPT-4o (Omni) vs Kimi K2

Compare GPT-4o (Omni) by OpenAI against Kimi K2 by Moonshot AI, in 5 community votes, kimi k2 wins 100% of head-to-head duels, tested across 34 shared challenges. Updated April 2026.

Which is better, GPT-4o (Omni) or Kimi K2?

Kimi K2 is the better choice overall, winning 100% of 5 blind community votes on Rival. GPT-4o (Omni) costs $2.5/M input tokens vs $0.57/M for Kimi K2. Compare their real outputs side by side below.

Key Differences Between GPT-4o (Omni) and Kimi K2

GPT-4o (Omni) is made by openai while Kimi K2 is from moonshotai. On pricing, GPT-4o (Omni) costs $2.5/M input tokens vs $0.57/M for Kimi K2. In community voting, In 5 community votes, Kimi K2 wins 100% of head-to-head duels.

In 5 community votes, Kimi K2 wins 100% of head-to-head duels. Kimi K2 leads in Conversation. Based on blind community voting from the Rival open dataset of 5+ human preference judgments for this pair.

Conversation: Kimi K2 wins 100% of votes
Our Verdict
Kimi K2
Kimi K2Winner
GPT-4o (Omni)
GPT-4o (Omni)Runner-up

Pick Kimi K2. In 5 blind votes, Kimi K2 wins 100% of the time. That's not luck.

Kimi K2 particularly excels in Conversation. Kimi K2 is 4.3x cheaper per token — worth considering if cost matters.

Clear winner
Writing DNA

Style Comparison

Similarity
83%

Kimi K2 uses 27.3x more emoji

GPT-4o (Omni)
Kimi K2
54%Vocabulary63%
18wSentence Length19w
0.72Hedging0.35
7.3Bold4.2
5.6Lists3.6
0.03Emoji0.68
1.40Headings0.61
0.26Transitions0.06
Based on 24 + 22 text responses
vs

Ask them anything yourself

GPT-4o (Omni)Kimi K2

279 AI models invented the same fake scientist.

We read every word. 250 models. 2.14 million words. This is what we found.

AI Hallucination Index 2026
Free preview13 of 58 slides
FAQ

Common questions