GPT-5 Codex vs Inception: Mercury

Compare GPT-5 Codex by OpenAI against Inception: Mercury by Inception, in 7 community votes, gpt-5 codex wins 100% of head-to-head duels, tested across 47 shared challenges. Updated April 2026.

Which is better, GPT-5 Codex or Inception: Mercury?

GPT-5 Codex is the better choice overall, winning 100% of 7 blind community votes on Rival. Compare their real outputs side by side below.

Key Differences Between GPT-5 Codex and Inception: Mercury

GPT-5 Codex is made by openai while Inception: Mercury is from inception. In community voting, In 7 community votes, GPT-5 Codex wins 100% of head-to-head duels.

In 7 community votes, GPT-5 Codex wins 100% of head-to-head duels. GPT-5 Codex leads in Image Generation, Web Design. Based on blind community voting from the Rival open dataset of 7+ human preference judgments for this pair.

Image Generation: GPT-5 Codex wins 100% of votes
Web Design: GPT-5 Codex wins 100% of votes
Our Verdict
GPT-5 Codex
GPT-5 CodexWinner
Inception: Mercury
Inception: MercuryRunner-up

Pick GPT-5 Codex. In 7 blind votes, GPT-5 Codex wins 100% of the time. That's not luck.

GPT-5 Codex particularly excels in Image Generation, Web Design.

Clear winner
Writing DNA

Style Comparison

Similarity
93%

GPT-5 Codex uses 3.4x more emoji

GPT-5 Codex
Inception: Mercury
64%Vocabulary55%
17wSentence Length40w
0.38Hedging0.39
2.3Bold4.9
3.5Lists3.8
0.15Emoji0.04
0.49Headings1.04
0.05Transitions0.03
Based on 13 + 17 text responses
vs

Ask them anything yourself

GPT-5 CodexInception: Mercury

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

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