Claude Sonnet
Latest: Claude Sonnet 5.5 · Sep 28, 2026
Anthropic · Claude Sonnet line · lightweight
Claude 3.7 Sonnet was released by Anthropic on February 24, 2025, as a lightweight model in the Claude Sonnet line.
The first Claude model that can either answer at once or think step by step first, with developers setting a thinking budget in the API, at the same price as Claude 3.5 Sonnet.
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Claude Sonnet 5.5 is the current model in this line. The card shows how long it has been since the last release against the line's usual gap and its recent ones — the rhythm, not a date.
Latest: Claude Sonnet 5.5 · Sep 28, 2026
Newest first. See the full line with every card →