New entriesSeptember 29, 2026Impact
Claude Sonnet 5.5 debuts at #4 on LMArena WebDev
Claude Sonnet 5.5 appeared on the LMArena WebDev leaderboard for the first time on Sep 29, 2026, placing #4 with 1699.
Why it matters
New entries near the top of LMArena WebDev move the Frontend & UI race on AIModelRace.
The details
- 1699 from 1,205 votes; early ratings carry wide confidence intervals and often move as votes accumulate.
Models in this story
Provenance: LMArena leaderboard published Sep 29, 2026; ratings from blind pairwise votes. Generated automatically from the published data. Sources: LMArena WebDev leaderboard · LMArena leaderboard dataset (CC BY 4.0) See the race.