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LLM ComparisonClaude 4.5 SonnetClaude 3 Opus

Claude 4.5 Sonnet vs Claude 3 Opus

Compare Claude 4.5 Sonnet and Claude 3 Opus. Build AI products powered by either model on Appaca.

Model Comparison

FeatureClaude 4.5 SonnetClaude 3 Opus
ProviderAnthropicAnthropic
Model Typetexttext
Context Window1,000,000 tokens200,000 tokens
Input Cost
$3.00/ 1M tokens
$15.00/ 1M tokens
Output Cost
$15.00/ 1M tokens
$75.00/ 1M tokens

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Strengths & Best Use Cases

Claude 4.5 Sonnet

Anthropic

1. Best-in-class coding performance

  • #1 on SWE-bench Verified (77.2% standard, 82.0% high-compute).
  • Excels at debugging, architecture, and multi-file code generation.
  • Maintains coherence for extremely long tasks (30+ hours).

2. State-of-the-art computer use & agents

  • Leads OSWorld at 61.4%.
  • Strongest model for agentic workflows, multi-step tool use, and real computer control.
  • Powering Claude Code, the new Claude Agent SDK, and Chrome agent actions.

3. Advanced reasoning & math

  • Large improvements across reasoning-heavy benchmarks (AIME, MMMLU, τ2-bench, Terminal-Bench).
  • Deep multi-step reasoning with extended or interleaved thinking.

4. High alignment & safety

  • Most aligned Claude model to date with reduced deception, hallucinations, sycophancy, and harmful compliance.
  • Strong protections against prompt injection for agentic tasks (ASL-3 safeguards).

5. Domain-expert performance

  • Notable gains in finance, law, medicine, and STEM tasks.
  • Trusted by early customers for long-context legal analysis, multi-file engineering, security research, and red-teaming.

Claude 3 Opus

Anthropic

1. Intelligence & Reasoning

  • Highest capability in the Claude 3 family
  • Near-human comprehension and fluency
  • Excels at MMLU, GPQA, GSM8K, advanced reasoning tasks

2. Complex Problem Solving

  • Best for research, strategy, multi-step planning
  • Handles ambiguous, open-ended tasks with ease

3. Vision & Multimodal Capabilities

  • Strong chart/graph understanding
  • Processes documents, technical diagrams, and dense visual data

4. Recall & Long-Context Reasoning

  • Near-perfect recall (>99% on NIAH benchmark)
  • Handles very large documents and multi-file workflows

5. Enterprise-Grade Accuracy

  • Significantly reduced hallucinations
  • High correctness rate for factual queries