Claude Opus 5.5
The hardest reasoning, coding, and long-horizon agentic tasks.
Claude Opus 5.5 supersedes Claude Opus 5.
What are Claude Opus 5.5's specs and price?
Claude Opus 5.5, built by Anthropic, ships a 1M-token context window and a 128K-token max output, released 2026-09. It supports text and vision input with a dedicated reasoning mode and costs $8.00 per million blended tokens, the 38th-cheapest of 42 models we track.
What are Claude Opus 5.5's specs?
| Context window | 1M tokens |
| Max output | 128K tokens |
| Modalities | text, vision |
| Extended thinking | Yes |
| Released | 2026-09 |
| Knowledge cutoff | 2026-06 |
| Provider | Anthropic |
Verified 2026-08-14 — source.
Where does Claude Opus 5.5 rank?
What are Claude Opus 5.5's strengths?
- Anthropic's strongest reasoning and coding
- 1M-token context
- Extended-thinking mode for complex agentic work
What else should you know about Claude Opus 5.5?
What are common questions about Claude Opus 5.5?
What is Claude Opus 5.5's context window?
Claude Opus 5.5 has a 1M-token context window and a 128K-token max output — the 11th-largest context of the 42 current models we track. Source: https://docs.anthropic.com/en/docs/about-claude/models, verified 2026-08-14.
Does Claude Opus 5.5 support vision or audio input?
Yes — Claude Opus 5.5 accepts vision input in addition to text.
Does Claude Opus 5.5 have a reasoning or extended-thinking mode?
Yes — Claude Opus 5.5 exposes a dedicated reasoning mode for multi-step problems.
When was Claude Opus 5.5 released, and what is its knowledge cutoff?
Claude Opus 5.5 was released 2026-09 with a knowledge cutoff of 2026-06.
How much does Claude Opus 5.5 cost, and who provides it?
Claude Opus 5.5 is served by Anthropic at $8.00/M blended tokens (3:1 input:output) — the 38th-cheapest of 42 current models. Full pricing breakdown: /llm-api-pricing/claude-opus-5-5.