Claude Sonnet 5.5 is now in StickyPrompts
Anthropic's new Sonnet is available in StickyPrompts. What it is good at, where it sits next to Opus 5.5, and how to try it on your own work today.
Anthropic released Claude Sonnet 5.5 on 28 September 2026, and it is available in StickyPrompts today. Pick it from the model picker in any chat, agent, prompt or workflow, the same way you pick any other model.
What Anthropic says it is for
Anthropic positions Sonnet 5.5 as the faster companion to Claude Opus 5.5, and says it is strongest at “well-scoped everyday tasks, fixing bugs, and creating polished documents, slides, and spreadsheets.” In other words: the steady middle of most working days, where you want a strong answer quickly rather than the deepest possible one.
The jump over Claude Sonnet 5 is large on the work that involves doing, not just writing. In Anthropic’s published results:
- Computer use (OSWorld 2.1): 80.1%, up from 57.0% for Sonnet 5.
- Real-world work across occupations (GDPval-AA v2.1): 1844, up from 1449, which Anthropic says is two points below Opus 5.5.
- Coding in an editor (CursorBench 4.0): 55.5%, up from 34.1%, within about two points of Opus 5.5.
Anthropic also says it generates output more than 30% faster than Sonnet 5, and it is the first Sonnet to launch with the cyber safeguards Anthropic uses for its most capable models.
Where it fits next to Opus 5.5
Think of the two as a pair. Opus 5.5 remains the model for long documents, hard analysis and the questions where you want the most careful answer available. Sonnet 5.5 is the one to reach for when the task is clear and you want the result sooner: a first draft, a spreadsheet formula, a tidy summary, a bug with a known shape.
The easiest way to decide for your own work is to try both on it.
Three ways to try it today
- Compare it on a real task. Open Compare Models, pick Sonnet 5.5 and Opus 5.5, and send the same brief to both. You see the answers side by side, with the time each one took.
- Make it your default. In Settings, Preferences, set your Preferred AI model to Claude Sonnet 5.5, and every new chat starts with it. You can still switch model in any chat.
- Put it on a schedule. Workflows and agents let you choose the model too, so the Monday digest or the daily store pulse can run on Sonnet 5.5 if it suits the job.
A response style carries over whatever the model, so if you already have a Board-ready or brand-voice style, the answers keep their shape when you switch.
Available in your workspace
Sonnet 5.5 appears wherever your workspace allows Anthropic models. If you can’t see it, your admins may limit providers per team in Model & Provider Access. See every model in StickyPrompts, or start a free trial and try it on your own work.
Source: Anthropic, Introducing Claude Sonnet 5.5.