GPT-5.3-Codex vs Claude Opus 4.1
Compare GPT-5.3-Codex by OpenAI against Claude Opus 4.1 by Anthropic, context windows of 400K vs 200K, tested across 27 shared challenges. Updated February 2026.
Compare GPT-5.3-Codex by OpenAI against Claude Opus 4.1 by Anthropic, context windows of 400K vs 200K, tested across 27 shared challenges. Updated February 2026.
27 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).
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 each other up!
All 5 jokes are unique - each one has a different setup and punchline with no repeats.
Tests an AI's ability to create detailed SVG illustrations of gaming hardware
Tests an AI's ability to simulate personalities and predict future trends
Tests an AI's humor and understanding of current events
Tests an AI's ability to generate a complete, working landing page
Recreate an interactive, classic Mario level in a single HTML file.
Tests an AI's UI design skills with theming support
Tests an AI's ability to engage in philosophical discourse about AI rights
Generate SVG art of a randomly chosen animal in a setting of its choosing.
Generate a unique and simple recipe with common ingredients.
Create a starter plan for improving long-term health.
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