Claude 5.5Translation site

What is Claude?

Claude is a family of large language models developed by Anthropic, designed for writing, programming, document analysis, and multi-step agent tasks. The current models support text and image input, text output, multilingual understanding, and tool invocation; it is important to distinguish between the models’ capabilities and the operational environments provided by applications such as Claude Web and Claude Code.Overview of Official Models

Version Changes and Selection

Opus 5.5, released on September 22, 2026, is designed for complex programming and knowledge work that requires continuous decision-making; Sonnet 5.5, released on September 28, is better suited for everyday tasks with clear requirements that call for rapid iteration, as well as bug fixes and the creation of office documents. Haiku 5.5, launched on October 7, focuses on high-frequency tasks such as classification, extraction, and summarization. Fable 5.1, released on September 1, is suitable for more challenging reasoning and long-process tasks; Mythos 5.1 is a restricted-access configuration and should not be considered a version available to all standard accounts.Opus Announcement,Sonnet Announcement,Haiku Announcement,Fable Product Page

What Tasks Is It Suitable For?

• Development Team:Understanding the codebase, identifying issues, writing tests, and compiling code review recommendations; complex changes still require testing and manual review.
• Knowledge Workers:Organize information by combining documents and images; draft proposals, analyze tables, and create presentation materials.
• App Developer:Integrate models into search, tools, and business processes; select models based on task difficulty; and manage permissions and usage costs.

How to use

1. go into Claude, Select a version based on the models available for your account, submit the materials, and specify the objectives, format, and prohibited actions.
2. Break down long tasks into deliverable steps; first have the model describe the plan, then review the output, references, and code test results.
3. API users create credentials in the Claude Console and specify a model ID via the Messages API, such as claude-opus-5-5; Start by evaluating quality, latency, and costs using a small number of real samples, then scale up usage.Getting Started with the API

Fees and Restrictions

Standard API pricing per million input/output tokens: $4/$20 for Opus 5.5, $2/$10 for Sonnet 5.5, and $10/$50 for Fable 5.1; separate rules apply for caching, tools, fast mode, and cloud platform billing. High-risk requests in the cybersecurity and biotechnology fields may trigger additional safeguards or model fallback; general product access does not grant restricted research permissions. Available models and quotas vary by subscription plan; the per-API unit price should not be interpreted as the total subscription cost. Access must comply with official supported regions and account requirements; long-context processing does not guarantee that every piece of information is used correctly, and critical facts and actions still require verification.Billing Information,Supported Regions

How to Choose Among Similar Options

Basis for Comparison:OpenAI Model Catalog,Gemini Official Introduction. When selecting a system, you should use your own task samples; do not treat the vendor’s benchmarks as a direct ranking of real-world performance. We recommend tracking completion rates, the number of manual reworks, and the total cost of the task. For open-ended tasks that require ongoing evaluation, start by assessing Opus; for clearly defined, small tasks, try Sonnet or Haiku.