AsOf

Claude Opus 5.5 · context window1M token context window

valid: Two independent sources agree, or a primary source states it: the record asserts this claim.asserted

What the statuses mean

Valid from
2026-09-22
Valid until
still holds
Published
2026-09-22
Recorded by AsOf
2026-11-07
Checked
2026-11-07 · its source page states the value and the date
Confidence
0.70

Sources

“September 22, 2026 We’ve launched Claude Opus 5.5 ( claude-opus-5-5 ), a model for long-running agentic coding and knowledge work. It has a 1M token context window by default, 128k max output tokens, and always-on adaptive thinking”— what the page says, read 2026-11-07

Cite this claim

Each form names the value, its as-of date (2026-09-22), the day you read it (2026-11-08), the claim's stable URL and id and its primary source. The URL never changes: a superseded claim stays at the same address.

Plain text
AsOf. "Claude Opus 5.5 context window: 1M token context window", as of 2026-09-22. Claim clm_473A8F3FAE68, https://asof.is/claim/clm_473A8F3FAE68, accessed 2026-11-08. Source: https://platform.claude.com/docs/en/release-notes/overview#2026-09-22.
APA
AsOf. (2026). Claude Opus 5.5 context window: 1M token context window (as of 2026-09-22) [Record clm_473A8F3FAE68]. Retrieved November 8, 2026, from https://asof.is/claim/clm_473A8F3FAE68 (source: https://platform.claude.com/docs/en/release-notes/overview#2026-09-22)
BibTeX
@misc{asof_clm_473A8F3FAE68,
  author = {AsOf},
  title = {Claude Opus 5.5 context window: 1M token context window},
  year = {2026},
  howpublished = {\url{https://asof.is/claim/clm_473A8F3FAE68}},
  note = {Claim clm\_473A8F3FAE68, as of 2026-09-22; source: https://platform.claude.com/docs/en/release-notes/overview\#2026-09-22},
  urldate = {2026-11-08}
}

On the record

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