Claude 3 Sonnet vs Claude Opus 4.5
How do these models stack up? Below is an expert side-by-side comparison of specifications, context window capacity, live pricing per million tokens, and standardized benchmark scores for Claude 3 Sonnet and Claude Opus 4.5.
Claude 3 Sonnet
Claude 3 Sonnet was Anthropic's balanced standard model in the first Claude 3 generation, optimized for a combination of response speed and general-purpose capabilities across writing, summarization, and question answering. Released in March 2024 alongside Opus and Haiku, it occupied the mid-tier positioning in the Claude 3 lineup. Claude 3 Sonnet has since been deprecated, and current use cases requiring similar capability-to-cost balance are best served by the Claude 4 Sonnet series, which offers substantially improved reasoning, context handling, and instruction following at competitive pricing.
Claude Opus 4.5
Claude Opus 4.5 is Anthropic’s frontier reasoning model optimized for complex software engineering, agentic workflows, and long-horizon computer use. It offers strong multimodal capabilities, competitive performance across real-world coding and...
Technical Specifications
| Specification | Claude 3 Sonnet | Claude Opus 4.5 |
|---|---|---|
| Provider | Anthropic | Anthropic |
| Context Window | 200,000 tokens | 200,000 tokens |
| Agent Suitability | N/A | 93/100 |
| Time to First Token (TTFT) | N/A | 550 ms |
| Deployment Model | N/A | managed api |
| Production Stability | stable | stable |
| API Available | Yes | Yes |
| Released Date | 2024-03-04 | 2025-11-24 |
API Pricing Comparison
Input Price per Million Tokens
Claude 3 Sonnet
$3.00
Claude Opus 4.5
$5.00
Output Price per Million Tokens
Claude 3 Sonnet
$15.00
Claude Opus 4.5
$25.00
Want to test both models live?
Run side-by-side prompt prompts in our dynamic Sandbox. Check execution speeds, latency metrics, and compute actual costs in real-time.
Benchmark Performance Metrics
Scores show the raw performance percentages verified across key evaluation suites. Higher bars indicate superior accuracy and capability in that domain.
Claude 3 Sonnet Quirks & Gotchas
No developer gotchas reported.
Claude Opus 4.5 Quirks & Gotchas
- ▸Deep analytical reasoning — best for structured problem-solving
- ▸200K context is limiting compared to 1M of Opus 4.6+ — upgrade for long-document tasks