Anthropic releases Claude Haiku 5.5 with adjustable effort setting

Anthropic released Claude Haiku 5.5 on 7 October 2026. Vendor figures show OSWorld rising from 15.7% to 72.4% and Terminal-Bench from 0% to 39.2%, with pricing at $0.10/$0.50 per MTok up to 100K tokens and average running cost down about 75%.

• OSWorld 2.1: 72.4% vs 15.7% for Haiku 4.5
• Terminal-Bench 4.0: 39.2% vs 0% for Haiku 4.5
• Pricing up to 100K tokens: $0.10/MTok input, $0.50/MTok output
• Average running cost about 75% lower due to new tokenizer