Anthropic launches Claude Sonnet 5.5: 30%+ faster, up to 30% cheaper per task, Terminal-Bench 4.0 jumps to 70.6%
aigclink · x · 2026-09-29
- Anthropic released Claude Sonnet 5.5, the second model in the Claude 5.5 family, positioned as a fast, low-cost complement to Opus 5.5 for well-scoped everyday tasks: bug fixing, polished docs/slides/spreadsheets, with strong design sense. Haiku 5.5 arrives in the coming weeks.
- Performance: 70.6% on Terminal-Bench 4.0 (agentic coding) vs Sonnet 5's 10.3%; just 2 points below Opus 5.5 on GDPval-AA; first Sonnet to beat Pokémon Red from screenshots alone, signaling stronger long-horizon and image understanding.
- Pricing: unchanged at $2/M input, $10/M output, $0.20/M cache reads — but it needs far fewer tokens per task, making it up to 30% cheaper than its predecessor.
- Speed: 30%+ faster generation, the fastest Sonnet yet.
- Safety: automated behavioral audits show alignment on par with or better than Sonnet 5 on most measures.
Related event: Anthropic Releases Claude Sonnet 5.5: 30% Faster at Lower Cost(47 posts)→
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