Which AI Model for Coding in 2026: GPT-5 vs Claude Opus 4.7 vs Gemini 2.5 Pro vs DeepSeek V4

For most production coding work in 2026, Claude Opus 4.7 is the default. GPT-5 wins greenfield speed, Gemini 2.5 Pro wins 2M-token sweeps, DeepSeek V4 wins cost.