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Language Model Provider: Anthropic

Claude Opus

Claude 3 Opus is Anthropic's most intelligent and capable model, released in March 2024 as the flagship of the Claude 3 family. Designed for complex tasks requiring advanced reasoning, deep analysis, and sophisticated problem-solving, Opus excels at graduate-level expert knowledge, mathematical reasoning, and complex coding challenges. As of October 2025, Claude 3 Opus remains the go-to choice for applications demanding maximum intelligence, achieving state-of-the-art results on challenging benchmarks including 96.4% on GPQA (expert-level reasoning) and 84.9% on HumanEval (code generation). Pricing: $15 per million input tokens, $75 per million output tokens.

Claude Opus
language-model claude anthropic advanced-reasoning

Overview

Claude 3 Opus represents the pinnacle of Anthropic's model capabilities, designed for tasks where intelligence matters more than speed or cost. Released in March 2024, it demonstrates near-human-level comprehension and fluency on complex tasks, excelling at graduate-level reasoning, expert-level knowledge synthesis, sophisticated coding, and nuanced analysis. With a 200K context window, Opus can process approximately 500 pages of text while maintaining deep understanding and generating thoughtful, well-reasoned responses. It's particularly valuable for research, strategic analysis, complex software architecture, advanced mathematics, and tasks requiring careful reasoning about edge cases and subtle implications.

Model Specifications (October 2025)

  • Claude 3 Opus: 200K context, $15/1M input, $75/1M output
  • Context: 200,000 tokens input, up to 4,096 tokens output
  • Speed: ~10-15 seconds for complex responses (prioritizes quality)
  • Vision: Advanced image analysis with detailed understanding
  • API: Available via Anthropic API, AWS Bedrock, Google Cloud Vertex AI
  • Training cutoff: August 2023

Key Capabilities

  • 200K token context window (approximately 500 pages of text)
  • Near-human performance on complex reasoning tasks
  • Advanced multimodal vision for detailed image analysis
  • Exceptional coding ability (HumanEval: 84.9%)
  • Graduate-level expert knowledge (GPQA: 96.4%)
  • Sophisticated mathematical reasoning (GSM8K: 95.0%)
  • Tool use and function calling for complex workflows
  • Constitutional AI for safe, nuanced responses
  • Strong multilingual capabilities for 20+ languages

Benchmarks & Performance

Claude 3 Opus achieves state-of-the-art performance across challenging benchmarks: 96.4% on GPQA (graduate-level expert reasoning), 84.9% on HumanEval (code generation), 95.0% on GSM8K (mathematical reasoning), 86.8% on MMLU (general knowledge), and 88.0% on MATH (competition-level mathematics). It outperforms GPT-4 on most intelligence benchmarks and demonstrates superior understanding of nuanced instructions, edge cases, and complex multi-step reasoning. Response quality consistently exceeds other models on tasks requiring deep analysis, though at the cost of higher latency (10-15 seconds typical) and expense.

Use Cases

  • Research and complex analysis requiring expert reasoning
  • Advanced software architecture and system design
  • Complex mathematical and scientific problem-solving
  • Legal document analysis and contract review
  • Strategic business analysis and planning
  • Medical literature review and synthesis
  • Advanced code generation and debugging
  • Multi-step reasoning and decision-making workflows
  • Detailed image analysis for specialized domains

Technical Specifications

Claude 3 Opus uses Anthropic's Constitutional AI framework with extensive RLHF (Reinforcement Learning from Human Feedback) for alignment and safety. Context window: 200K tokens input, 4,096 tokens output (upgradeable to 8K via API parameter). API rate limits: Free tier (50 requests/min), Build tier ($5+ spend: 1000 RPM), Scale tier (2000 RPM with priority). Model training cutoff: August 2023. Temperature range: 0-1, with 1.0 as default. Supports streaming responses, batch processing, prompt caching, and extended analysis mode. Vision capabilities include OCR, chart analysis, diagram understanding, and detailed visual reasoning.

Pricing (October 2025)

Claude 3 Opus: $15 per 1M input tokens, $75 per 1M output tokens. Example costs: 50K tokens input + 2K tokens output = $0.90 per request. Prompt caching reduces repeat input costs by 90% ($1.50 per 1M cached tokens). Batch API offers 50% discount with 24-hour processing window ($7.50/$37.50). Free tier: $5 credit for new accounts. Enterprise pricing available for volume commitments over $100K/month. Note: Opus is 60x more expensive than Haiku and 5x more expensive than Sonnet for output tokens - use strategically for tasks requiring maximum intelligence.

Code Example

import anthropic

client = anthropic.Anthropic(api_key="sk-ant-...")

# Basic Claude 3 Opus usage for complex reasoning
message = client.messages.create(
    model="claude-3-opus-20240229",
    max_tokens=4096,
    messages=[{
        "role": "user",
        "content": "Analyze the architectural tradeoffs between microservices and monolithic design for a financial trading platform handling 10K TPS, considering latency, consistency, deployment complexity, and operational overhead. Provide specific recommendations."
    }]
)

print(message.content[0].text)

# Advanced vision analysis
import base64

with open("medical_scan.jpg", "rb") as img:
    image_data = base64.b64encode(img.read()).decode("utf-8")

message = client.messages.create(
    model="claude-3-opus-20240229",
    max_tokens=2048,
    messages=[{
        "role": "user",
        "content": [
            {"type": "image", "source": {"type": "base64", "media_type": "image/jpeg", "data": image_data}},
            {"type": "text", "text": "Analyze this medical imaging scan. Identify any notable features, potential concerns, and areas requiring closer examination. Be thorough and specific."}
        ]
    }]
)

print(message.content[0].text)

# Complex multi-step reasoning with tool use
tools = [{
    "name": "search_research_papers",
    "description": "Search academic databases for research papers",
    "input_schema": {
        "type": "object",
        "properties": {
            "query": {"type": "string"},
            "database": {"type": "string", "enum": ["pubmed", "arxiv", "ieee"]},
            "year_range": {"type": "string"}
        },
        "required": ["query", "database"]
    }
}, {
    "name": "analyze_statistical_significance",
    "description": "Perform statistical analysis on research data",
    "input_schema": {
        "type": "object",
        "properties": {
            "data": {"type": "array"},
            "test_type": {"type": "string", "enum": ["t-test", "anova", "chi-square"]}
        },
        "required": ["data", "test_type"]
    }
}]

message = client.messages.create(
    model="claude-3-opus-20240229",
    max_tokens=4096,
    tools=tools,
    messages=[{
        "role": "user",
        "content": "Conduct a comprehensive literature review on transformer attention mechanisms for computer vision, published since 2022. Identify key innovations, compare methodologies, and assess statistical significance of reported improvements."
    }]
)

print(message.content)

# Prompt caching for long context (saves 90% on repeated input)
message = client.messages.create(
    model="claude-3-opus-20240229",
    max_tokens=2048,
    system=[
        {
            "type": "text",
            "text": "You are an expert legal analyst.",
        },
        {
            "type": "text",
            "text": "<legal_context>" + long_legal_document + "</legal_context>",
            "cache_control": {"type": "ephemeral"}
        }
    ],
    messages=[{
        "role": "user",
        "content": "Summarize the liability provisions in section 7."
    }]
)

print(message.content[0].text)

Comparison: Opus vs Sonnet vs Haiku

Claude 3 Opus provides maximum intelligence and reasoning capability at premium pricing ($15/$75 per 1M tokens). Claude 3.5 Sonnet offers the best balance of intelligence, speed, and cost for most applications ($3/$15 per 1M tokens) and has largely replaced Opus for general use. Claude 3.5 Haiku excels at speed and cost-efficiency for high-volume tasks ($0.25/$1.25 per 1M tokens). For October 2025: Use Opus only when maximum intelligence is essential and cost is secondary (complex research, expert analysis, critical decisions). For most applications, Claude 3.5 Sonnet with extended thinking mode provides comparable results at lower cost and faster speed.

When to Choose Opus

  • Complex research requiring graduate-level reasoning
  • Critical decisions where maximum intelligence matters
  • Advanced mathematical or scientific problem-solving
  • Sophisticated code architecture and system design
  • Detailed analysis of complex, nuanced documents
  • Expert-level domain knowledge synthesis
  • When cost is secondary to quality and accuracy
  • Tasks where Sonnet's performance is insufficient

Professional Integration Services by 21medien

21medien offers expert Claude Opus integration services for applications requiring maximum intelligence, including research automation, expert analysis systems, complex decision support, and advanced reasoning workflows. Our team specializes in prompt engineering for complex tasks, implementing cost-optimization strategies (prompt caching, selective routing), and building hybrid systems that route between models based on task complexity. We provide architecture consulting, evaluation frameworks for measuring reasoning quality, and production deployment strategies. Contact us for custom Claude Opus solutions tailored to your most demanding AI requirements.

Resources

Official documentation: https://docs.anthropic.com/en/docs/about-claude/models | API reference: https://docs.anthropic.com/en/api | Model comparison: https://docs.anthropic.com/en/docs/about-claude/model-comparison | Pricing: https://www.anthropic.com/pricing