AnalysisAI ModelsJuly 2, 2026

Opus 4.8 outperforms Sonnet 5 on DeepSWE benchmark

A Reddit comparison using Datacurve's DeepSWE benchmark finds Opus 4.8 scores higher at every effort tier and is cheaper than Sonnet 5 at matched effort levels. The analysis suggests Sonnet 5 offers no performance advantage over the more cost-effective Opus 4.8.

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