Gemini 3 vs Claude Opus 4.5 vs Codex MAX: Which AI Builds Your App Best?
December 5, 2025 • Engineering • 14 min read
We tested the three frontier AI coding models head-to-head. Claude Opus 4.5 leads benchmarks at 80.9% on SWE-bench (first to break 80%). Codex MAX can code autonomously for 24+ hours straight. Gemini 3 Pro tops the WebDev Arena with 1487 Elo.
Our take: Claude for quality, Codex for endurance, Gemini for speed and cost.