Claude Opus 5.5
Anthropic · · 21 days after Claude Mythos 5.1
Partially verified
0 of 2 published values traced to a source1 primary source, 0 archived2 not researched yet
Why this status
Newly added. Sources are not archived and no value has been traced to one yet — run `npm run enrich`.
What these states mean · How records are judged · Has this record changed?
Anthropic launched Claude Opus 5.5 (claude-opus-5-5) for long-running agentic coding and knowledge work, with a 1M token context window by default, 128k max output tokens and always-on adaptive thinking, priced at $4 / $20 per million input / output tokens against $5 / $25 for Claude Opus 5. Available on the Claude API, Amazon Bedrock, Claude Platform on AWS, Google Cloud and Microsoft Foundry.
Details
| Released | September 22, 2026 |
|---|---|
| Company | Anthropic |
| Family | Claude |
| Lineage | after Claude Opus 5 |
| Era | Agentic systems |
| Type | Language model · LLM |
| Modalities | Not recorded |
| Capabilities | Reasoning, Agentic, Coding |
| Weights | Proprietary |
| Licence | Not applicable — proprietary |
| Context window | 1M tokens |
| Parameters | Not researched |
Current information, elsewhere
This record is a historical one: every figure above is traced to a dated primary source. For what is true today — live pricing, current rankings, availability — these are better maintained than anything here could be.
- Current price and providers OpenRouter ↗
- Current benchmark scores Artificial Analysis ↗
Sources
Record status: partly verified · confidence 60/100 · 1 of 1 primary
Newly added. Sources are not archived and no value has been traced to one yet — run `npm run enrich`.
- platform.claude.com Official documentation
Primary means published by the organisation that made the model. Verified records require at least one.
Claude family
- Claude 1 March 14, 2023
- Claude 2 July 11, 2023
- Claude 3 Opus March 4, 2024
- Claude 3.5 Sonnet June 21, 2024
- Claude 3.7 Sonnet February 24, 2025
- Claude Opus 4 May 22, 2025
- Claude Sonnet 4.5 September 29, 2025
- Claude Haiku 4.5 October 15, 2025
- Claude Opus 4.5 November 24, 2025
- Claude Opus 4.6 February 5, 2026
- Claude Sonnet 4.6 February 17, 2026
- Claude Opus 4.7 April 16, 2026
- Claude Opus 4.8 May 28, 2026
- Claude Fable 5 June 9, 2026
- Claude Mythos 5 June 9, 2026
- Claude Sonnet 5 June 30, 2026
- Claude Opus 5 July 24, 2026
- Claude Fable 5.1 September 1, 2026
- Claude Mythos 5.1 September 1, 2026
- Claude Opus 5.5 September 22, 2026
- Claude Sonnet 5.5 September 28, 2026
- Claude Haiku 5.5 October 7, 2026
What changed from Claude Opus 5
Compared with the previous release in this series. A field appears only when both records state a value — where one does not, it is listed as uncomparable rather than dropped, because a gap in our research is not a finding about the model.
Not comparable: Parameters (not researched on both releases); Capabilities and modalities (not researched on both releases)
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