# clm_34EE9AAE8E66

subject: Claude Opus 4.8 (/record/claude-opus-4-8.md)  
predicate: context_window  
value: 1M token context window  
valid_from: 2026-05-28  
valid_to: null  
published: 2026-05-28  
recorded: 2026-11-11  
confidence: 0.70  
status: valid  
assertable: true  
superseded_by: null  
last_updated: 2026-11-11  
cite: AsOf. "Claude Opus 4.8 context window: 1M token context window", as of 2026-05-28. Claim clm_34EE9AAE8E66, https://asof.is/claim/clm_34EE9AAE8E66, accessed 2026-11-11. Source: https://platform.claude.com/docs/en/release-notes/overview#2026-05-28.  
checked: 2026-11-11 · its source page states the value and the date  

> May 28, 2026  We’ve launched Claude Opus 4.8 ( claude-opus-4-8 ), our most capable model. Claude Opus 4.8 supports a 1M token context window by default on the Claude API, Amazon Bedrock, Google Cloud, and Microsoft Foundry, 128k max output tokens

What https://platform.claude.com/docs/en/release-notes/overview#2026-05-28 says, word for word.

## Sources

- https://platform.claude.com/docs/en/release-notes/overview#2026-05-28 (primary, Anthropic, published 2026-05-28)

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