Claude Opus 5.5
AvailableAn Anthropic model with a 1M-token context window, image input and tool calling. On the Anthropic API since September 22, 2026.
Access details: Anthropic API
The model ID to use in API requests.
claude-opus-5-5Updated Sep 23, 2026
Capabilities & limits
- Context window
- 1M
- Maximum output
- 128K
- Image input
- Supported
- Tool calling
- Supported
- Structured output
- Supported
Pricing
USD / 1M tokens- Input
- $4.00
- Output
- $20.00
Standard rates per million tokens. Discounts and long-context rates, where offered, are on Anthropic's pricing page.
Full rate card 5 rates
All prices in USD.
Input tokens
$4.00 per 1M tokens- Claude API global standard
Output tokens
$20.00 per 1M tokens- Claude API global standard
Cache reads
$0.20 per 1M tokens- prompt caching
5 minute cache writes
$5.00 per 1M tokens- prompt caching
- 5 minute duration
1 hour cache writes
$8.00 per 1M tokens- prompt caching
- 1 hour duration
Batch API requests are discounted 50% on input and output.
Price history
Sep 23, 2026
Input $4.00 per million tokens
Sep 23, 2026
Output $20.00 per million tokens
Technical details
- Parameters
- Not published
- Active parameters
- Not published
- Architecture
- Not published
- Training / knowledge cutoff
- Jun 2026
- Input modalities
- Text, image
- Output modalities
- Text
From Anthropic
Official announcement ↗How they describe it
For long-running agentic coding and knowledge work
What they say is new
It performs at the level of Claude Fable 5.1 on most work and costs 40% less to run than Opus 5.
Release & lifecycle
- First available
- Sep 22, 2026
- available
- As of Sep 23, 2026