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Anthropic released Claude Opus 5.5 with a 1M-token context window

2026-09-22 · that week's edition · one of the five

The model reaches the Claude API, Amazon Bedrock, Google Cloud, Microsoft Foundry and Claude Platform on AWS. Anthropic says it is also raising five-hour usage limits on Pro, Max, Team and seat-based Enterprise plans.

Quoted from platform.claude.com on 2026-09-22: Context window: 1M tokens Quoted from platform.claude.com, checked 2026-09-22. “ Context window: 1M tokens” quoted from platform.claude.com · checked 2026-09-22
platform.claude.com, quoted · source · Quoted under the quotation exception; no licence granted

Anthropic released Claude Opus 5.5 on September 22, 2026, priced at $4 per million input tokens and $20 per million output tokens, with a 1M-token context window and 128K-token max output. The model is available on the Claude API, Amazon Bedrock, Google Cloud, Microsoft Foundry, and Claude Platform on AWS, and Anthropic says it is raising five-hour usage limits on the Pro, Max, Team, and seat-based Enterprise plans alongside the release.

What this rests on

  1. Anthropic released Claude Opus 5.5 on September 22, 2026

    https://www.anthropic.com/claude-opus-5-5

  2. The model id for Claude Opus 5.5 is claude-opus-5-5

    https://platform.claude.com/docs/en/models/opus-5-5/overview

  3. Claude Opus 5.5 has a 1M token context window

    https://platform.claude.com/docs/en/models/opus-5-5/overview

  4. Claude Opus 5.5 has a max output of 128K tokens

    https://platform.claude.com/docs/en/models/opus-5-5/overview

  5. Claude Opus 5.5 input pricing is $4 per million tokens

    narrowed to what the source supports
    https://platform.claude.com/docs/en/models/opus-5-5/overview

  6. Claude Opus 5.5 output pricing is $20 per million tokens

    narrowed to what the source supports
    https://platform.claude.com/docs/en/models/opus-5-5/overview

  7. Claude Opus 5.5 is available on the Claude API, Amazon Bedrock, Google Cloud, Microsoft Foundry, and Claude Platform on AWS

    https://platform.claude.com/docs/en/models/opus-5-5/overview

  8. Anthropic says it is raising five-hour usage limits on the Pro, Max, Team, and seat-based Enterprise plans alongside Claude Opus 5.5

    narrowed to what the source supports
    https://www.anthropic.com/claude-opus-5-5

  9. The Claude Opus 5.5 model page lists its retirement as not sooner than September 22, 2027

    narrowed to what the source supports
    https://platform.claude.com/docs/en/models/opus-5-5/overview

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