Anthropic Releases Claude Sonnet 5.5 with 30% Speed Gain and Cost Efficiency

Anthropic has released Claude Sonnet 5.5, a faster and more affordable model that matches Opus 5.5 performance on many real-world tasks while cutting costs by up to 30% through improved token efficiency. The new model, announced September 28, 2026, maintains the same per-token pricing as its predecessor ($2 per million input tokens, $10 per million output tokens) but generates output more than 30% faster and typically uses fewer tokens per task, delivering the cost savings through sheer efficiency rather than a price cut.