Anthropic released Claude Haiku 5.5 on October 7, 2026, calling it “the cheapest, fastest, and most capable small model we’ve ever released.” It is available on the Claude Platform as claude-haiku-5-5 and on Amazon Web Services, Google Cloud and Microsoft Azure. It is the first Haiku-class model with an adjustable effort setting.
Pricing is $0.10 per million input tokens and $0.50 per million output tokens for requests up to 100,000 tokens, rising to $0.50 and $2.50 above that, against $1.00 and $5.00 for Haiku 4.5. Anthropic says it costs about 75 percent less to run than Haiku 4.5 on average. In the same post it halved Sonnet 5.5’s cache-read price, which it says makes Sonnet 5.5 about 20 percent cheaper on most agentic work.
Anthropic’s reported scores include 72.4 percent on the offline subset of OSWorld 2.1 (Haiku 4.5: 15.7 percent; GPT-6 Luna: 48.9 percent; Sonnet 5.5: 83.9 percent), 39.2 percent on Terminal-Bench 4.0 against 0.0 percent for Haiku 4.5, and 45.9 percent on Humanity’s Last Exam without tools. Anthropic positions it for high-volume work such as summaries, classification and database queries, and as a subagent alongside Opus 5.5 and Sonnet 5.5, while saying the larger models remain better for complex agentic coding.
Why it matters: the jump from 15.7 to 72.4 percent on a computer-use benchmark in one generation, at a tenth of the input price, moves agentic work that needed a mid-tier model a year earlier into the cheapest tier, which changes the economics of running many agents at once.
What it does not show: every figure is Anthropic’s own, OSWorld 2.1 is reported on an offline subset, and the post does not state a context window or a safety level designation.