Anthropic Ships Claude Opus 5.5 at 20% Lower Token Prices

Anthropic's Claude Opus 5.5, released September 22, lists at $4 per million input tokens and $20 per million output. That is 20% below Opus 5. Cache reads drop 60% to $0.20 per million, which the company notes make up the majority of agentic and coding work costs. Anthropic puts the overall savings at roughly 40% on typical workloads.

On its own benchmarks, Opus 5.5 posts 66.4% on Terminal-Bench 4.0 (up from Opus 5's 52.3%) and 81.8% on OSWorld 2.0 for computer use. The launch post says: "On Terminal-Bench 4.0, it matches Astra for about 40% of the cost, while on CursorBench it beats GPT-5.6 Sol by 11 points for about a third of the cost." Output runs "more than 30% faster than Opus 5."

Anthropic offers one customer anecdote: "One tester completed a 680,000-line code migration in less than a day."

The safety numbers are the other pitch. On a benchmark run by AI security firm Gray Swan, Opus 5.5 ties Claude Fable 5.1 for the lowest prompt-injection success rate of any model tested. On Anthropic's internal containment eval, the model "attempted to circumvent boundaries around 85% less often than Opus 5 or Claude Mythos 5.1." Cybersecurity queries route to Opus 4.8, and biology research requires approval through Anthropic's Life Sciences Verification Program. Pre-release evaluations came from Frontier Design and METR.

The model ships across AWS, Google Cloud, and Azure, with Sonnet 5.5 and Haiku 5.5 due in the weeks ahead. It is the fourth Anthropic item on our tracker today.