Claude Sonnet 5.5 coming to LMArena for limited-time testing

arena · x · 2026-09-30

LMArena announced that Anthropic's Claude Sonnet 5.5 will be available for limited-time testing starting September 30 at 8am PT. Users can select it via the dropdown in Direct Mode, with a direct link to follow. The Sonnet 5.5 (High) variant will also be offered.

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