Compare Claude Opus 4 by Anthropic against GPT-5.3-Codex by OpenAI, context windows of 200K vs 400K, tested across 35 shared challenges. Updated February 2026.
35 fights queued
Tests an AI's ability to solve a simple but potentially confusing logic puzzle
Tests an AI's randomness and creativity
Sure—here are 5 jokes:
Why don’t skeletons fight each other?
They don’t have the guts.
I told my computer I needed a break…
Now it won’t stop sending me KitKat ads.
Why did the math book look sad?
It had too many problems.
I used to play piano by ear…
Now I use my hands.
Why did the scarecrow win an award?
Because he was outstanding in his field.
✅ How many are unique? 5 (all of them).
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.
Create a 3D building and driving game in a single self-contained HTML file using Three.js. Tests an AI's ability to combine 3D graphics, game logic, and UI interactions on the web.
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 a single-page, self-contained HTML webapp using Tailwind CSS for a randomly chosen category/industry/niche.
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