Compare GPT-5.3-Codex by OpenAI against xAI: Grok 4 by xAI, context windows of 400K vs 256K, tested across 38 shared challenges. Updated February 2026.
38 fights queued
Tests an AI's ability to make educated estimates based on technical knowledge
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 ability to simulate personalities and predict future trends
Tests an AI's humor and understanding of current events
Tests an AI's ability to write in distinct character voices
Tests an AI's ability to generate a complete, working landing page
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
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