Anthropic
Operational· 100% uptime, 7 days

Claude Opus 5.5 API

The Claude Opus 5.5 API at 65% below list price, on one OpenAI-compatible key.

Price per 1M tokens65%off
Input
$1.40$4.00
Output
$7.00$20.00
Cached input
$0.07
Get your API keyTry it in the playground
Model IDclaude-opus-5-5
chat.py
from openai import OpenAI
client = OpenAI(
    base_url="https://api.zurelay.com/v1",
    api_key="YOUR_ZURELAY_KEY",
)
stream = client.chat.completions.create(
    model="claude-opus-5-5",
    messages=[{"role": "user", "content": "Explain quicksort in two sentences."}],
    stream=True,
)
for chunk in stream:
    if chunk.choices:
        print(chunk.choices[0].delta.content or "", end="")

Base URL https://api.zurelay.com/v1. Works with any OpenAI SDK, and the Anthropic SDK and Claude Code.

Context window
1M tokens
Max output
128K tokens
Input
Text, Image
Output
Text
Released
Sep 22, 2026
Uptime, 7 days
100%

Pricing

Claude Opus 5.5 API pricing. A fraction of the list price.

Pay as you go from prepaid credit, with no subscription and no minimum. Requests that fail are never billed.

RatezurelayAnthropic listYou save
Input
per 1M tokens
$1.40$4.0065%off
Output
per 1M tokens
$7.00$20.0065%off
Cached input
per 1M tokens
$0.07——

One rate at every prompt length, up to the full 1M context window. Streaming, tool calls and structured outputs cost nothing extra.

Savings calculator

Move the sliders to your monthly usage.

Input tokens per month50M
Output tokens per month10M
zurelay
$140.00
Anthropic list price
$400.00
You save every month$260.00

$3,120 a year

Overview

What is Claude Opus 5.5?

Claude Opus 5.5 is Anthropic's current Opus model, built for long-running agentic coding and knowledge work. The zurelay Claude Opus 5.5 API serves it through an OpenAI-compatible or Anthropic-compatible endpoint at 65% below Anthropic's list price, for teams that want Opus-level results without Opus-level bills.

Claude Opus 5.5 is Anthropic's Opus-tier model, released on September 22, 2026. Anthropic describes it as built for long-running agentic coding and knowledge work, and its model guide suggests starting with Opus 5.5 for most workloads. On zurelay, the Claude Opus 5.5 API uses the model ID claude-opus-5-5 and costs $1.40 per 1M input tokens and $7.00 per 1M output tokens.

Anthropic says Opus 5.5 performs at the level of Claude Fable 5.1 on most work. It also says the model generates output more than 30% faster than Claude Opus 5 and costs about 40% less to run on typical workloads. Early testers pointed to large code migrations, audits and refactors. Anthropic also reports clearer writing than earlier models and more precise reading of dense charts, diagrams and screenshots.

The specs: a 1M-token context window, up to 128K output tokens per request, text and image input, and text output. Adaptive thinking is always on. The model decides how much to reason, and you steer depth, latency and cost with the effort setting (low, medium, high, xhigh or max). The default is medium, one level lower than on Claude Opus 5, so raise it explicitly for hard problems.

Two API changes matter if you are migrating. Thinking cannot be disabled, so lower effort where you used to turn it off. Forced tool choice (any, or a specific named tool) returns an error, so keep tool choice on auto and use strict tool schemas or structured outputs when you need guaranteed JSON. Prompt caching works with a 512-token minimum cacheable prompt.

Strengths

Where Claude Opus 5.5 shines. And what teams build with it.

01

Long-running agentic coding

Built for multi-step coding agents that plan, call tools and verify their work. Anthropic highlights large migrations, audits, refactors and code review.

02

1M tokens of context

Fit a large codebase or document set in one request. On Anthropic's current tokenizer, 1M tokens is roughly 555k English words.

03

Reasoning you can dial

Adaptive thinking is always on. Set effort per route, from low for quick answers to max when correctness matters more than cost.

04

Sharper vision

Reads values off dense charts, diagrams and screenshots more precisely than Claude Opus 5, often without extra image tools.

Use cases

  • Coding agents

    Run refactors, migrations and code review with tool calls, and stream progress back to your IDE, CLI or CI job.

  • Codebase and document analysis

    Load a repository, a contract set or a research corpus into the 1M-token window and ask questions across all of it.

  • Knowledge work

    Turn messy inputs into reports, analyses and structured JSON. Anthropic says Opus 5.5 leads its lineup on knowledge work.

  • Charts and screenshots

    Extract numbers from dashboards, charts and UI screenshots for reporting, QA or browser automation.

Get started

Call Claude Opus 5.5 in three steps.

No waitlist and no new SDK. If your code already talks to OpenAI, it already talks to zurelay.

  1. 1

    Create a key

    Sign up, add credit and create an API key. Set a monthly budget or a rate limit per key if you like.

    Get your API key
  2. 2

    Point your SDK at zurelay

    Change the base URL. Everything else in your code stays the same.

    https://api.zurelay.com/v1
  3. 3

    Use claude-opus-5-5

    Send chat completions as usual. Streaming, tool calls and usage reporting work as you expect.

    claude-opus-5-5

Works with the tools you already use

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FAQ

Claude Opus 5.5 API questions.

Anything else, write to sales@zurelay.com and an engineer will answer.

How much does the Claude Opus 5.5 API cost on zurelay?

zurelay charges $1.40 per 1M input tokens and $7.00 per 1M output tokens, with cached input at $0.07. Anthropic's list price is $4.00 input and $20.00 output, so you save 65%. Prices are per token, with the same rate across the full context window.

Is there a cheaper Claude Opus API than Anthropic's?

Yes. zurelay serves claude-opus-5-5 at 65% below Anthropic's list price. It is the same model, not a smaller substitute. You keep your code and change the base URL and key.

How do I call Claude Opus 5.5 with the OpenAI SDK?

Create a zurelay API key, set the base URL to https://api.zurelay.com/v1 and set the model to claude-opus-5-5. Chat completions, streaming and tool calls use the request shapes you already know from OpenAI. One Opus-specific rule: leave tool_choice on auto, because forcing a tool (required, or a named function) returns an error on this model.

Can I use the Anthropic SDK or Claude Code with zurelay?

Yes. zurelay also serves the Anthropic Messages API. Set the Anthropic SDK's base URL, or ANTHROPIC_BASE_URL for Claude Code, to https://api.zurelay.com with no /v1, because the client adds /v1/messages itself. Authenticate with your zurelay key.

How do I get a Claude Opus 5.5 API key?

Sign up at zurelay and create a key in the dashboard. The same key works for Claude Opus 5.5 and every other model in the catalog. You can give each key a spend limit, a requests-per-minute cap and an expiry date.

What is the Claude Opus 5.5 context window?

Claude Opus 5.5 has a 1M-token context window and returns up to 128K output tokens per request. For long outputs, stream the response so the connection stays active while tokens arrive.

What is Claude Opus 5.5 best at?

Anthropic built it for long-running agentic coding and knowledge work: multi-step agents, large migrations and refactors, code review, analysis and writing. It also reads charts and screenshots well. For short, well-scoped tasks where speed matters most, Claude Sonnet 5.5 is often enough.

Does the zurelay Claude Opus 5.5 API support streaming, and what are the rate limits?

Streaming works on both chat completions and the Messages API, using server-sent events. You set your own requests-per-minute cap and spend limit on each key. If a route errors, times out or hits a rate limit, zurelay retries on another route for the same model, and failed attempts are not billed.

Are Claude Opus 5.5 responses on zurelay identical to Anthropic's API?

Your requests run on Claude Opus 5.5 itself, and zurelay never swaps in a different or smaller model. Output is sampled, so the exact wording varies from call to call on any API, but capability and behavior are the model's own. zurelay is an independent service and is not affiliated with or endorsed by Anthropic.

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