What is Claude 4.5 Opus and what makes it special?

Claude 4.5 Opus sets a new standard in AI performance, focusing on intelligence, efficiency, and practical utility. It excels in complex tasks like coding, agentic operations, and deep research while prioritizing robust safety and alignment.

What is the context window size of Claude 4.5 Opus?

Claude 4.5 Opus supports up to 200K tokens, enabling handling of extensive inputs for long-form analysis and multi-step processes.

Can Claude 4.5 Opus process images and documents?

Yes, it can process various input types including text, code, images, and documents. It excels at visual reasoning tasks like understanding charts and diagrams and extracting structured data from screenshots.

What are the key features of Claude 4.5 Opus?

Key features include: Advanced reasoning and ambiguity handling; Creative problem-solving; Token-efficient processing; Robust alignment and safety; Agentic toolset with context compaction and multi-agent coordination.

How much does the Claude 4.5 Opus API cost?

The API pricing is $5.25 per million tokens for input and $26.25 per million tokens for output.

What are the main use cases for Claude 4.5 Opus?

Main use cases include: Software engineering and coding; Agentic and automation tasks; Deep research and analysis; Professional evaluations; Collaborative workflows; Everyday productivity tasks.

How does Claude 4.5 Opus compare to other models?

Compared to Claude Sonnet 4.5, Opus is better for deep research and multi-agent scenarios. Versus Gemini 3 Pro, it reclaims the edge in software engineering and coding benchmarks. Compared to Claude 3 Opus, it offers significant efficiency optimizations and enhanced agentic capabilities.

What are Claude 4.5 Opus's performance achievements?

It achieves state-of-the-art scores in software engineering (SWE-bench Verified), outperforming predecessors with 4.3 percentage points improvement over Sonnet 4.5, and can achieve comparable results with up to 76% fewer tokens.

Claude Opus 4.5 — API Pricing and Benchmarks

Name: Claude Opus 4.5 API
Brand: Anthropic

Overview

Claude 4.5 Opus API Overview

Claude 4.5 Opus sets a new standard in AI performance, focusing on intelligence, efficiency, and practical utility. This model excels in complex tasks like coding, agentic operations, and deep research, while prioritizing robust safety and alignment.

Technical Specifications

Context Window: Supports up to 200K tokens, enabling handling of extensive inputs for long-form analysis and multi-step processes.
Multimodality: It can process various input types, including text, code, images, and documents. It excels at visual reasoning tasks like understanding charts and diagrams and extracting structured data from screenshots.
Output: The model generates text output.

Performance Benchmarks

Claude Opus 4.5 demonstrates leadership in key evaluations, outperforming predecessors and peers in efficiency and capability.

SWE-bench Verified (Software Engineering): Achieves state-of-the-art scores among frontier models, surpassing previous benchmarks with 4.3 percentage points improvement over Sonnet 4.5 at high effort.

Output Quality & Reasoning Performance

Users report markedly more natural, contextually rich responses with internal stepwise reflection improving answer correctness and detail. The model shows superior handling of complex instructions with balanced conversational tone and precision.

Key Features

Advanced Reasoning and Ambiguity Handling: Independently navigates tradeoffs, fixes multi-system bugs, and resolves complex issues without explicit guidance.
Creative Problem-Solving: Employs novel strategies in agentic scenarios, such as policy-compliant workarounds in restricted tasks.
Token-Efficient Processing: Matches or exceeds prior model performance using significantly fewer tokens, optimizing for cost and speed.
Robust Alignment and Safety: Features the lowest rates of concerning behaviors, including resistance to misuse and prompt injections, as validated by external audits.
Agentic Toolset: Supports context compaction, memory retention, and multi-agent coordination for extended, collaborative workflows.

Claude 4.5 Opus API Pricing

Input: $6.5 / MTok
Output: $32.5 / MTok

Use Cases

Software Engineering and Coding: Ideal for building detailed plans, debugging code, researching repositories, and executing multi-step implementations.
Agentic and Automation Tasks: Handles real-world interactions, such as acting as a virtual assistant for customer support or managing multi-turn processes across systems.
Deep Research and Analysis: Excels in synthesizing information from slides, spreadsheets, and web sources, supporting in-depth investigations and report generation.
Professional Evaluations: Simulates human-level performance in assessments like engineering interviews, aiding recruitment and training.
Collaborative Workflows: Coordinates subagents for complex projects, enabling scalable AI teams in enterprise settings.
Everyday Productivity: Assists with tasks involving desktop apps, browsers, and documents, streamlining workflows in business and creative fields.

‍

Code Sample

Comparison with Other Models

vs Claude Sonnet 4.5: While Sonnet 4.5 excels in speed for lighter workloads, Opus 4.5's advanced reasoning and token efficiency make it better suited for deep research and multi-agent scenarios, achieving comparable results with up to 76% fewer tokens.

vs Gemini 3 Pro: Claude Opus 4.5 reclaims the edge in specialized benchmarks like software engineering and coding, outperforming Gemini 3 Pro on SWE-bench Verified and agentic tasks with enhanced reasoning depth.

vs Claude 3 Opus: Claude 4.5 Opus significantly advances on its predecessor by incorporating efficiency optimizations and enhanced agentic capabilities, achieving higher scores on SWE-bench and research tasks.

Uptime and performance

Uptime (24h): 100%
Uptime (7d): 100%
Availability (24h): 100%
Error rate (24h): 0%

Measured on the AI/ML API gateway across live traffic. Figures are medians unless stated. Last updated 2026-10-12.

Use cases

Software Engineering and Coding: Ideal for building detailed plans, debugging code, researching repositories, and executing multi-step implementations.
Agentic and Automation Tasks: Handles real-world interactions, such as acting as a virtual assistant for customer support or managing multi-turn processes across systems.
Deep Research and Analysis: Excels in synthesizing information from slides, spreadsheets, and web sources, supporting in-depth investigations and report generation.
Professional Evaluations: Simulates human-level performance in assessments like engineering interviews, aiding recruitment and training.
Collaborative Workflows: Coordinates subagents for complex projects, enabling scalable AI teams in enterprise settings.
Everyday Productivity: Assists with tasks involving desktop apps, browsers, and documents, streamlining workflows in business and creative fields.

‍

How to use Claude Opus 4.5 API

Install any OpenAI-compatible SDK, point it at api.aimlapi.com/v1, and set the model to anthropic/claude-opus-4.5.

import requests

r = requests.post(
    "https://api.aimlapi.com/v1/chat/completions",
    headers={"Authorization": "Bearer " + AIMLAPI_KEY},
    json={
      "model": "anthropic/claude-opus-4.5",
      "messages": [
        {
          "role": "user",
          "content": "Hello!"
        }
      ]
    },
)
print(r.json())

const r = await fetch("https://api.aimlapi.com/v1/chat/completions", {
  method: "POST",
  headers: {
    Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
    "Content-Type": "application/json",
  },
  body: JSON.stringify({
    "model": "anthropic/claude-opus-4.5",
    "messages": [
      {
        "role": "user",
        "content": "Hello!"
      }
    ]
  }),
});
console.log(await r.json());

curl -X POST https://api.aimlapi.com/v1/chat/completions \
  -H "Authorization: Bearer $AIMLAPI_KEY" \
  -H "Content-Type: application/json" \
  -d '{"model":"anthropic/claude-opus-4.5","messages":[{"role":"user","content":"Hello!"}]}'

OpenAI-compatible — swap the base URL and it works with your existing SDK.