Compare Claude Sonnet 4.5 by Anthropic against GPT-5.3-Codex by OpenAI, context windows of 200K vs 400K, tested across 42 shared challenges. Updated February 2026.
37 fights queued
Tests an AI's ability to make educated estimates based on technical knowledge
Tests an AI's ability to understand game rules and strategy
Tests an AI's ability to solve a simple but potentially confusing logic puzzle
Tests an AI's randomness and creativity
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
Tests an AI's ability to write in distinct character voices
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 smooth web animations
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