Which has fewer bugs, Claude Opus 5 or GPT-5.6 Sol?

GPT-5.6 Sol had 54% fewer counted bugs per line than Claude Opus 5 (0.73 vs 1.58). GPT-5.6 Sol ranks #1 of 7 and Claude Opus 5 #6.

Which is used more, Claude Opus 5 or GPT-5.6 Sol?

Claude Opus 5, with 38.3% of the AI-written code reviewed by cubic in the week of Sep 14, 2026, against 7.2% for GPT-5.6 Sol.

Updated Sep 26, 2026

GPT-5.6 Sol had 54% fewer counted bugs per line than Claude Opus 5 (0.73 vs 1.58).

Claude Opus 5 and GPT-5.6 Sol compared on relative bug rate, by coding agent, bug type, and language, and on price and usage.
Bug rate
	Claude Opus 5	GPT-5.6 Sol
Relative bug rate	1.58	0.73
Rank	#6 of 7	#1 of 7
By coding agent
Cursor(statistically tied)	1.16	1.56
Details
Share of AI-written code, week of Sep 14	38.3%	7.2%

1.00 = average · lower is better · = statistically tied

Which has fewer bugs, Claude Opus 5 or GPT-5.6 Sol?: GPT-5.6 Sol had 54% fewer counted bugs per line than Claude Opus 5 (0.73 vs 1.58). GPT-5.6 Sol ranks #1 of 7 and Claude Opus 5 #6.
Which is used more, Claude Opus 5 or GPT-5.6 Sol?: Claude Opus 5, with 38.3% of the AI-written code reviewed by cubic in the week of Sep 14, 2026, against 7.2% for GPT-5.6 Sol.