Which AI model is best for coding? A hands-on comparison
10 hours ago
- Claude Opus 5.5 is the best overall AI model for coding as of September 2026, based on leaderboards and a custom test.
- GPT-5.6 Sol is a close second for precise, well-specified changes and uses the fewest tokens.
- Edge cases (like fence-tracking in Markdown) separate models when spec tests are saturated.
- A custom bake-off test showed all six models passed spec tests, but only three (Opus 5.5, GPT-5.6 Sol, Grok 4.7) passed all edge cases consistently.
- Model performance varies between runs; multiple rounds (at least three) are needed for reliable comparison.
- Token cost and speed differ significantly: Opus 5.5 was fastest, Grok 4.7 slowest and most verbose.
- The article recommends testing models on your own code rather than relying solely on leaderboards.
- For most work, Claude Opus 5.5 Medium is recommended; for precise changes, GPT-5.6 Sol; for frontend, Claude Fable 5.1; for high-volume simple tasks, GPT-6 Luna.