# clm_0BB378E5F905

subject: Claude (/record/claude.md)  
predicate: context_window  
value: 1M token context window  
valid_from: 2026-02-17  
valid_to: 2026-04-20  
published: 2026-02-17  
recorded: 2026-11-01  
confidence: 0.70  
status: superseded  
assertable: true  
superseded_by: clm_849B1F10CFD0  
last_updated: 2026-11-01  
cite: AsOf. "Claude context window: 1M token context window", as of 2026-02-17 (until 2026-04-20). Claim clm_0BB378E5F905, https://asof.is/claim/clm_0BB378E5F905, accessed 2026-11-09. Source: https://platform.claude.com/docs/en/release-notes/overview#2026-03-13.  
checked: 2026-11-01 · its source page states the value and the date  

> February 17, 2026  We’ve launched Claude Sonnet 4.6 , our latest balanced model combining speed and intelligence for everyday tasks. Sonnet 4.6 delivers improved agentic search performance while consuming fewer tokens. Sonnet 4.6 supports extended thinking and a 1M token context window (beta).

What https://platform.claude.com/docs/en/release-notes/overview#2026-03-13 says, word for word.

## Sources

- https://platform.claude.com/docs/en/release-notes/overview#2026-03-13 (primary, Anthropic, published 2026-03-13)
- https://platform.claude.com/docs/en/release-notes/overview#2026-02-17 (primary, Anthropic, published 2026-02-17)

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