EDUCATION & TRAINING
How to Read the June 2026 SWE-bench Leaderboard
Dev.to Machine Learning
About This Tutorial
What the leaderboard actually says - and what to do with it Open any coding-model tracker this week and the top of the table looks decisive. Per third-party trackers as of 1 June 2026, the SWE-bench Verified leaderboard reads Claude Mythos Preview at 93.9%, Claude Opus 4.8 at 88.6%, and Claude Opus 4.7 (Adaptive) at 87.6%. OpenAI stopped self-reporting Verified in February 2026, so GPT-5.5 only appears on independent trackers, where it lands around 88.7%. Read at a glance, that is a near-perfect machine that fixes nine in ten real bugs. Read properly, it is not.