Claude Sonnet
Latest: Claude Sonnet 5.5 · Sep 28, 2026
Anthropic · Claude Sonnet line · lightweight
Claude Sonnet 5 was released by Anthropic on June 30, 2026, as a lightweight model in the Claude Sonnet line.
Replaced Sonnet 4.6 as the default model on Anthropic's Free and Pro plans, priced at $2 per million input tokens and $10 per million output tokens.
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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
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