Claude 3.5 Sonnet
Summary
Claude 3.5 Sonnet is a proprietary language model from Anthropic, released on 9 Sept 2025. It accepts text and images and generates text, with a 200K-token context window and up to 8K output tokens per response.
Balanced Claude model for coding, analysis, agent workflows, and cost control
Last verified 4 Oct 2026. Every figure on this page links to its source.
Specifications
| Developer | Anthropic |
|---|---|
| Release date | 9 Sept 2025 [models.dev] |
| Status | Generally available [models.dev] |
| Weights | Proprietary (API only) [models.dev] |
| Context window | 200K (200,000 tokens) [models.dev] |
| Max output | 8K tokens [models.dev] |
| Knowledge cutoff | 30 Apr 2024 [models.dev] |
| Input | Text and images [models.dev] |
| Output | Text [models.dev] |
| Reasoning mode | Yes [models.dev] |
| Tool calling | Yes [models.dev] |
| Structured output | No [models.dev] |
Claude 3.5 Sonnet API pricing by provider
USD per million tokens. Sorted by input price.
We do not currently track a paid API listing for this model.
Frequently asked questions
What is the context window of Claude 3.5 Sonnet?
Claude 3.5 Sonnet has a context window of 200,000 tokens (200K) and can generate up to 8,200 tokens in a single response, according to models.dev.
Is Claude 3.5 Sonnet open source?
No. Claude 3.5 Sonnet is a proprietary model; Anthropic has not released its weights.
When was Claude 3.5 Sonnet released?
Anthropic released Claude 3.5 Sonnet on 9 Sept 2025, according to models.dev.
Change history
No changes detected since we started tracking this model. We re-check every source daily.