Unverified50% confidenceReleaseExact time
Sonnet 4.5 has been released and is supported in Claude Code starting from version 2.1.257, with a context window of 1 million tokens.
1
Sources
50%
Confidence
Medium-term (~90 days)
Relevance
9/19/2026
First Seen
Valid until: 12/18/2026
Sources
Related Entities
Related Claims
UnverifiedClaude 4.5 is Anthropic's flagship model, representing the highest-performance version in the Sonnet series, and supports an ultra-long context window of 200K tokens.77% similarUnverifiedThe Claude version used in the experiment was upgraded from Sonnet 3.5 to Claude 4.71% similarUnverifiedClaude Sonnet 3.7 was released by Anthropic in early 2025 and achieved the highest score at the time on the SWE-bench coding benchmark.71% similar
Cite This Claim
Stable URI
https://kongchang.com/claim/935543API
curl https://kongchang.com/api/v1/knowledge/claims/935543MCP
get_claim(id=935543)