Claude Sonnet 5.5評測：跑分贏Opus 5.5，價格沒漲 | Claude Sonnet 5.5 Review: Beats Opus 5.5, Same Price

9月 30, 2026

By Kit 小克 | AI Tool Observer | 2026-09-30

🇹🇼 Claude Sonnet 5.5評測：跑分贏Opus 5.5，價格沒漲

Claude Sonnet 5.5是Anthropic在2026年9月28日、Opus 5.5發布僅6天後推出的新模型，主打「更快、更便宜」的日常工作夥伴定位。最讓人意外的是，官方跑分顯示Claude Sonnet 5.5在部分項目居然超越自家旗艦Opus 5.5，而且價格完全沒漲。

什麼是Claude Sonnet 5.5？

Claude Sonnet 5.5是Claude 5.5系列的第二款模型，定位是處理修bug、日常寫程式、文件與試算表這類「範圍明確」的工作，把Opus 5.5留給更複雜的任務。

官方主打三個提升

輸出速度比Sonnet 5快超過30%
因為需要的token與工具呼叫次數變少，單一任務成本最多省30%
agentic coding（自主寫程式）能力明顯增強

Claude Sonnet 5.5跑分表現如何？

在Terminal-Bench 4.0（測試AI自主操作終端機的能力）上，Claude Sonnet 5.5拿到70.6%，相較Sonnet 5的10.3%是巨幅跳躍，甚至贏過Opus 5.5的66.4%。這代表在需要連續呼叫工具、跑迴圈修正的場景，Sonnet 5.5可能比旗艦更好用。

在衡量真實知識型工作的GDPval-AA v2.1測試中，Sonnet 5.5拿下1844分，只小輸Opus 5.5的1846分，卻大幅超越Sonnet 5的1449分。換句話說，它已經逼近旗艦等級的實用表現。

價格會漲嗎？

不會。Claude Sonnet 5.5維持Sonnet 5原本的定價：每百萬輸入token 2美元、輸出10美元，比Opus 5.5便宜約5倍。這代表開發者可以直接把API裡的model參數換成新版本，成本結構完全不變，卻拿到更快、更強的模型。

該不該升級？

如果你原本就用Claude API做coding agent、自動化工作流，這次升級幾乎沒有理由拒絕——同價格、更快、更省token。如果你原本用Opus 5.5處理agentic coding，現在可以考慮換成Sonnet 5.5省下大量成本，把Opus留給真正需要深度推理的任務。值得一提的是，這是第一款內建Anthropic網路安全防護、並具備阻擋推理過程被提取的分類器的Sonnet模型，安全性也沒有打折。

好不好用，試了才知道。

🇺🇸 Claude Sonnet 5.5 Review: Beats Opus 5.5, Same Price

Claude Sonnet 5.5 is Anthropic's newest model, released September 28, 2026 — just six days after Opus 5.5. It's pitched as the fast, cheap workhorse for well-scoped tasks, but the surprising part is that on some benchmarks, Claude Sonnet 5.5 actually beats the flagship Opus 5.5, at unchanged pricing.

What is Claude Sonnet 5.5?

Claude Sonnet 5.5 is the second model in the Claude 5.5 family, built for bug fixes, everyday coding, documents, and spreadsheets — leaving the heaviest reasoning work to Opus 5.5.

Three headline improvements

Output generated more than 30% faster than Sonnet 5
Up to 30% lower cost per task, thanks to fewer tokens and tool calls
Noticeably stronger agentic coding performance

How does Claude Sonnet 5.5 perform on benchmarks?

On Terminal-Bench 4.0, which tests autonomous command-line agent work, Claude Sonnet 5.5 scores 70.6% — a massive jump from Sonnet 5's 10.3%, and actually ahead of Opus 5.5's 66.4%. For workflows built on long tool-call loops, Sonnet 5.5 may outperform the flagship.

On GDPval-AA v2.1, a benchmark for real knowledge work, Sonnet 5.5 scores 1844, just two points behind Opus 5.5's 1846 and roughly 400 points above Sonnet 5's 1449 — putting it within striking distance of flagship-level usefulness.

Did the price go up?

No. Claude Sonnet 5.5 keeps Sonnet 5's exact pricing: per million input tokens and per million output tokens — roughly a fifth of what Opus 5.5 costs. Developers can swap the model parameter in the API and get a faster, stronger model at the same cost structure.

Should you switch?

If you're already running coding agents or automation on the Claude API, there's little reason not to upgrade — same price, faster, cheaper per task. If you've been using Opus 5.5 for agentic coding specifically, Sonnet 5.5 may let you cut costs significantly and reserve Opus for tasks that truly need deep reasoning. It's also the first Sonnet model to ship with Anthropic's cyber safeguards and classifiers that block attempts to extract its reasoning — security wasn't sacrificed for speed.

好不好用，試了才知道 — you only know if it's good once you've tried it.

Sources / 資料來源

常見問題 FAQ

Claude Sonnet 5.5比Opus 5.5便宜多少？

價格不變，維持每百萬輸入token 2美元、輸出10美元，約為Opus 5.5的五分之一。

Sonnet 5.5值得從Sonnet 5升級嗎？

值得。Terminal-Bench分數從10.3%跳到70.6%，agentic coding能力大幅提升，價格卻沒變。

Sonnet 5.5和Opus 5.5哪個更適合寫程式？

官方跑分顯示Sonnet 5.5在Terminal-Bench上甚至贏過Opus 5.5，適合當日常寫程式主力。

Claude Sonnet 5.5安全性如何？

是首款內建網路安全防護、並具備阻擋推理過程被提取分類器的Sonnet模型。

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