Claude 3.5 Sonnet, released by Anthropic in June 2024, sits at the top of Anthropic's model lineup and competes directly with GPT-4o and Gemini 1.5 Pro.
**Reasoning & Coding**
Claude 3.5 Sonnet scores 92% on HumanEval, surpassing GPT-4o's 90.2%. On SWE-bench, which tests real-world software engineering tasks, it achieves 49% — the highest of any publicly available model at launch.
**Context Window**
With a 200,000-token context window, it can process entire codebases, long legal documents, or book-length content in a single prompt.
**Writing Quality**
Anthropic's training approach results in responses that feel more nuanced and less formulaic than competitors. Long-form writing, analysis, and summarization are standout strengths.
**Safety**
Anthropic's Constitutional AI approach means Claude is less likely to produce harmful outputs and more likely to acknowledge uncertainty honestly.
**Pricing**
$3 per million input tokens and $15 per million output tokens via API. Available on Claude.ai with a free tier.
**Verdict**
If coding assistance and long-document analysis are your priorities, Claude 3.5 Sonnet is arguably the best model available.