Claude Sonnet 5 is officially live.
This is the new best daily AI model in the world.
Here's everything you need to know:
It's the most agentic Sonnet model Anthropic has ever shipped, closing the gap with Opus 4.8 while staying significantly cheaper.
→ Default model for Free and Pro plans, available everywhere now
→ Launch pricing: $2/$10 per million tokens (input/output) through August 31, then $3/$15 after
→ Lower hallucination and sycophancy rates than Sonnet 4.6
→ Better at refusing malicious requests and resisting prompt injection attacks
→ Available in Claude Code, Claude Platform, and via API as claude-sonnet-5
Huge cost curve reduction.
Sonnet 5 now sits in the same performance range that used to require Opus-class pricing.
Now we just need Fable 5 back!
Introducing Claude Sonnet 5, our most agentic Sonnet yet.
It makes plans, uses tools like browsers and terminals, and runs autonomously at a level that just a few months ago required larger and more expensive models.
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.@milesdeutscher Sonnet 5 costs more than Opus 4.8 on the Artificial Analysis Intelligence Index
Jul 1, 2026 · 1:57 AM UTC
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