Anthropic · Claude · Fable · Mythos

Claude 4.5 Sonnet

Released 29 Sep 2025 · 55 days after Claude 4.1 Opus

Intelligence

—

no index score yet

Price

$6.00

per 1M tokens, 3:1 in/out · $3 in / $15 out

Speed

—

not measured

Weights

Closed

US lab

Anthropic’s best score over time