MajorAnthropicNew Launch
Claude Sonnet 5.5 released, replacing Sonnet 5
Anthropic introduced Claude Sonnet 5.5 with a new API ID (claude-sonnet-5-5) and extended knowledge/training cutoffs (Jun 2026). The prior Sonnet 5 model is replaced, so users pinned to claude-sonnet-5 should migrate to the new ID.
Sep 28, 2026 (UTC)Views:5
Impact Assessment
Cost0
Reliability1
Migration3
Quality3
Compliance0
Sources
docs
Anthropic Models Docs
Claude Sonnet 5.5
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