# Claude Opus 5.5 API

Claude Opus 5.5 is Anthropic's model for long-running agentic coding and knowledge work and its suggested starting point for most workloads, with a 1M-token context window and up to 128K output tokens; list price $4.00 in / $20.00 out per 1M tokens, provider list as at 1 November 2026.

- Provider: Anthropic
- Model ID: claude-opus-5-5
- Type: Chat
- Region: AU (can be pinned to Sydney or Melbourne on request)
- Context window: 1,000,000 tokens
- Max output: 128,000 tokens
- Modalities: text, vision, tools, reasoning
- Endpoints: OpenAI Chat Completions https://api.seedrise.ai/v1; Anthropic Messages https://api.seedrise.ai
- Prices checked: 1 November 2026

## Provider list price

Provider list price as at 1 November 2026, per 1M tokens. AUD at a reference rate of 1 USD = 1.53 AUD; invoices use the rate on the day.

| Token type | USD | AUD |
|---|---:|---:|
| Input | 4.00 | 6.12 |
| Output | 20.00 | 30.60 |
| Cached input | 0.20 | 0.31 |

Your Seedrise rate is quoted per account against this list price. Request a rate card: https://seedrise.ai/contact?model=claude-opus-5-5

Pinning to an Australian region carries the provider's regional premium on top of the list price shown.

Launch rate (global routing): 3.60 input · 18.00 output per 1M tokens, 10% below Anthropic's published list price, for rate card requests by 31 Jan 2027. Terms (https://seedrise.ai/launch-offer)

Marked AU: can be pinned to Sydney or Melbourne on request, where the Australian-region list price is $4.40 in / $22.00 out per 1M tokens (cache reads $0.22). Without pinning it runs on the provider's global routing at the standard list price.

## Strengths

- Adaptive thinking always on, with medium as the default effort level
- 1M-token context window billed at the same per-token rate across the full window
- Cache reads list at $0.20 per 1M tokens
- Can be pinned to Sydney or Melbourne for teams with data residency requirements

## Typical use cases

- Claude Code and other coding agents working across a whole repository
- Long-running knowledge work: drafting, analysis and review over large document sets
- Agent workflows with many tool calls
- A default model for teams standardising on one Claude tier

## Quickstart

A first request with curl. Replace sk-... with your Seedrise key.

```bash
curl https://api.seedrise.ai/v1/chat/completions \
  -H "Authorization: Bearer sk-..." \
  -H "Content-Type: application/json" \
  -d '{"model":"claude-opus-5-5","messages":[{"role":"user","content":"Hello"}]}'
```

OpenAI SDK, Python:

```python
from openai import OpenAI

client = OpenAI(base_url="https://api.seedrise.ai/v1", api_key="sk-...")

r = client.chat.completions.create(
    model="claude-opus-5-5",
    messages=[{"role": "user", "content": "Summarise this contract in three bullets."}],
)
print(r.choices[0].message.content)
```

Claude Code talks Anthropic Messages, so it points at the root URL:

```bash
export ANTHROPIC_BASE_URL="https://api.seedrise.ai"
export ANTHROPIC_AUTH_TOKEN="sk-..."                     # your Seedrise key
export ANTHROPIC_API_KEY=""                             # clear any personal key
export ANTHROPIC_DEFAULT_OPUS_MODEL="claude-opus-5-5"
export ANTHROPIC_DEFAULT_SONNET_MODEL="claude-sonnet-5-5"
export ANTHROPIC_DEFAULT_HAIKU_MODEL="claude-haiku-5-5"
export CLAUDE_CODE_SUBAGENT_MODEL="claude-sonnet-5-5"
export CLAUDE_CODE_DISABLE_NONESSENTIAL_TRAFFIC=1
claude
```

Full guide: https://seedrise.ai/claude-code

## Where it runs

AU: Can be pinned to Sydney or Melbourne on request. Pinning is set per key, not per request.

Claude in Australia: https://seedrise.ai/claude-australia

## Related models

- [Claude Fable 5.1](https://seedrise.ai/models/claude-fable-5-1): US$10.00 input · US$50.00 output per 1M tokens, Global
- [Claude Sonnet 5.5](https://seedrise.ai/models/claude-sonnet-5-5): US$2.00 input · US$10.00 output per 1M tokens, AU
- [Claude Haiku 5.5](https://seedrise.ai/models/claude-haiku-5-5): US$0.10 input · US$0.50 output per 1M tokens, AU
- [GPT-6.1 Sol](https://seedrise.ai/models/gpt-6.1-sol): US$2.00 input · US$10.00 output per 1M tokens, Global
- [Gemini 4 Argon](https://seedrise.ai/models/gemini-4-argon): US$2.00 input · US$10.00 output per 1M tokens, Global
- [Kimi K3.1 Pro](https://seedrise.ai/models/kimi-k3.1-pro): US$2.00 input · US$10.00 output per 1M tokens, Global

## FAQ

### What is the model ID for Claude Opus 5.5?

Use claude-opus-5-5 as the model field, with no vendor prefix. It works on the OpenAI-compatible endpoint at https://api.seedrise.ai/v1 and on Anthropic Messages at https://api.seedrise.ai. GET /v1/models returns the IDs your key can call.

### How does the Seedrise rate for Claude Opus 5.5 compare to the list price?

Anthropic's list price as at 1 November 2026 is US$4.00 per 1M input tokens and US$20.00 per 1M output tokens. Seedrise quotes rates per account against the provider's published list price for the same routing. Volume and committed tiers sit below list. Australian-region routing carries the provider's regional premium.

### What is the context window and max output of Claude Opus 5.5?

Claude Opus 5.5 has a context window of 1,000,000 tokens and a maximum output of 128,000 tokens, per the provider documentation checked on 1 November 2026.

### Can Claude Opus 5.5 run in Australia?

Yes. Claude Opus 5.5 can be pinned to Sydney or Melbourne on request. Pinning is set per key, not per request, and carries the provider's regional premium.

### Does Claude Opus 5.5 support 1M context on Seedrise?

Yes. Opus 5.5 has a 1M-token context window with up to 128K output tokens per request, and the provider bills the full window at the same per-token rate, so a 900K-token prompt costs the same per token as a short one.

### What does Australian-region pinning cost for Claude Opus 5.5?

The Australian-region list price is $4.40 in / $22.00 out per 1M tokens, against $4.00 / $20.00 on global routing, as at 1 November 2026. Your Seedrise rate is quoted per account for whichever routing you choose.

Seedrise is an independent provider and is not affiliated with or endorsed by Anthropic. Claude is a trademark of Anthropic, PBC.

Model names are trademarks of their respective providers.

Source: https://seedrise.ai/models/claude-opus-5-5