Claude Sonnet 5.5
The balanced middle model of Anthropic's Claude 5.5 family, released September 28, 2026, at half the price of Opus 5.5.
- Made by
- Anthropic
- Released
- Type
- Flagship
- Status
- Live
- How to get it
- Claude apps and the Claude API
- Good for
- Everyday writingCodingBusiness tasks
What it is
Sonnet sits between Opus (most capable) and Haiku (fastest) in Anthropic’s lineup. Sonnet 5.5 came out on September 28, 2026, with a 1 million token context window.
What it means for you
For most day-to-day work, Sonnet gives you most of Opus’s quality for half the API price.
Use cases this model is good for
How to summarize a long PDF or contract with AI (without missing the important parts)
You have a 60-page report or contract and need the key points, numbers and risks today, without reading every page.
Best pick: ClaudeUp to 2h savedHow to clean messy spreadsheet data with AI
Your spreadsheet has duplicate rows, five spellings of the same company and three date formats, and the report is due tomorrow.
Best pick: ChatGPTAbout 1h saved
