# clm_5045E2C6B4ED

subject: Claude Sonnet 4 (/record/claude-sonnet-4.md)  
predicate: context_window  
value: 1M token  
valid_from: 2025-08-12  
valid_to: 2026-04-30  
published: 2025-08-12  
recorded: 2026-11-13  
confidence: 0.70  
status: superseded  
assertable: true  
superseded_by: null  
last_updated: 2026-11-14  
cite: AsOf. "Claude Sonnet 4 context window: 1M token", as of 2025-08-12 (until 2026-04-30). Claim clm_5045E2C6B4ED, https://asof.is/claim/clm_5045E2C6B4ED, accessed 2026-11-14. Source: https://platform.claude.com/docs/en/release-notes/overview#2025-08-12.  
checked: 2026-11-14 · its source page states the value and the date, as read by an AI model  

> August 12, 2025 We’ve launched beta support for a 1M token context window in Claude Sonnet 4 on the Claude API and Amazon Bedrock.

What https://platform.claude.com/docs/en/release-notes/overview#2025-08-12 says, word for word.

## Sources

- https://platform.claude.com/docs/en/release-notes/overview#2025-08-12 (primary, Anthropic, published 2025-08-12)
- https://platform.claude.com/docs/en/release-notes/overview (primary, Anthropic (Claude Platform release notes))

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