The new mid-tier AI model offers near-Opus performance at a fraction of the cost.

Claude Sonnet 5 brings near-Opus 4.8 agentic performance at a mid-tier price, from $2/$10 per million tokens until August 31. Here's what is new.

Anthropic's Claude Sonnet 5, codenamed Fennec, is reportedly being prepared for release on OpenRouter after months of delays and speculation.