Anthropic Releases Claude Sonnet 5.5 — A Fast and Affordable...

Anthropic Releases Claude Sonnet 5.5 — A Fast and Affordable Addition to Opus 5.5

Anthropic has released Claude Sonnet 5.5, the second model in the 5.5 lineup, which the company says responds more than 30% faster than Sonnet 5, costs up to 30% less per task, and, according to Artificial Analysis, has nearly matched the flagship Opus 5.5 in work tasks at unchanged prices.

Compiled by Sergey KostenchukPublished 2026-09-28Updated 2026-09-29

2026-09-28 Research Anthropic

🤖 Anthropic Releases Claude Sonnet 5.5 — A Fast and Affordable Addition to Opus 5.5

The model is designed for clearly defined everyday tasks: fixing bugs, documents, presentations, and spreadsheets. According to Anthropic, it responds more than 30% faster than Sonnet 5 and costs up to 30% less per task. Prices remain the same: $2/$10 per million input and output tokens.

🌍 Sonnet 5.5 has nearly caught up to the flagship: in GDPval-AA (Artificial Analysis benchmark) — 1844 points vs. 1846 for Opus 5.5, in Terminal-Bench 4.0 — 70.6% vs. 66.4%. Input tokens are half the price: $2 vs. $4 per million.

👤 The model is available in Claude apps, via the API as claude-sonnet-5-5, and on AWS, Google Cloud, and Azure. For the first time among Sonnet models, it completed Pokémon Red, navigating using only screen screenshots.

Source 1: https://www.anthropic.com/claude-sonnet-5-5 Source 2: https://www-cdn.anthropic.com/870c8f525702625d2c62fc6dd04c857e3250bec1/Claude%20Sonnet%205.5%20System%20Card.pdf

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