Updated
Which AI model writes the most logic bugs?
As of Nov 14, 2026, Grok 4.7 had the highest rate of logic bugs (1.45, 45% above the all-model rate). GPT-6 Luna had the lowest (0.28, 72% below average).
| Rank | Model | Rate |
|---|---|---|
| 1 | GPT-6 Luna | 0.28 |
| 2 | GPT-6.1 Sol | 0.61 |
| 3= (statistically tied) | GPT-6 Astra | 0.85 |
| 4= (statistically tied) | Claude Sonnet 5.5 | 0.85 |
| 5= (statistically tied) | Claude Fable 5.1 | 0.93 |
| 6 | Claude Opus 5.5 | 1.04 |
| 7 | Grok 4.7 | 1.45 |
1.00 = all-model rate · lower is better · = statistically tied