Compare Claude Opus 4 by Anthropic against GPT-5 Codex by OpenAI, in 4 community votes, claude opus 4 and gpt-5 codex are closely matched, tested across 31 shared challenges. Updated April 2026.
Claude Opus 4 and GPT-5 Codex are closely matched based on 4 community votes. Compare their real outputs side by side below.
Claude Opus 4 is made by anthropic while GPT-5 Codex is from openai. In community voting, In 4 community votes, Claude Opus 4 and GPT-5 Codex are closely matched.
In 4 community votes, Claude Opus 4 and GPT-5 Codex are closely matched. Claude Opus 4 leads in Web Design. Based on blind community voting from the Rival open dataset of 4+ human preference judgments for this pair.
Votes are tied. GPT-5 Codex is newer and likely incorporates more recent improvements.
Claude Opus 4 particularly excels in Web Design.
Claude Opus 4 uses 5.0x more transitions
vsAsk them anything yourself
279 AI models invented the same fake scientist.
We read every word. 250 models. 2.14 million words. This is what we found.
31 fights queued
Tests an AI's ability to solve a simple but potentially confusing logic puzzle
I need to work through this step-by-step.
Given information:
Since Sally is one of the sisters that each brother has, and each brother has 2 sisters total, that means th ere must be exactly 2 sisters in the family.
The 2 sisters are:
Therefore, Sally has 1 sister.
Tests an AI's randomness and creativity
Here are 5 jokes:
Why don't scientists trust atoms? Because they make up everything!
What do you call a bear with no teeth? A gummy bear!
Why did the scarecrow win an award? He was outstanding in his field!
What do you call a fake noodle? An impasta!
Why don't eggs tell jokes? They'd crack up!
All 5 jokes are unique - each one has a different setup and punchline, covering different topics (atoms/scie nce, bears, scarecrows, pasta, and eggs).
Tests an AI's ability to generate vector graphics
Tests an AI's ability to create detailed SVG illustrations of gaming hardware
Tests an AI's humor and creative writing ability
Recreate an interactive, nostalgic Pokémon battle UI in a single HTML file.
Recreate an interactive, classic Mario level in a single HTML file.
Tests an AI's ability to replicate an existing UI with Tailwind CSS
Tests an AI's ability to create interactive web elements
Tests an AI's ability to create a detailed world map in SVG format
Generate SVG art of a randomly chosen animal in a setting of its choosing.
Generate a unique and simple recipe with common ingredients.
19+ more head-to-head results. Free. Not a trick.
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