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# Anthropic Announces Claude Opus 4 and Claude Sonnet 4
- URL: https://www.theleftshift.com/anthropic-announces-claude-opus-4-and-claude-sonnet-4/
- Published: 2025-05-22T17:58:42.000Z
- Updated: 2025-05-22T17:58:42.000Z
- Description: It claims that Claude Opus 4 is the world’s best coding model, capable of working autonomously for up to seven hours—nearly a full corporate workday
- Author: The Left Shift Bureau
- Tags: AI Startups, #a42

AI startup Anthropic announced its latest language models—Claude 4.0 Sonnet and Claude 4.0 Opus—at the Code w/Claude event on Thursday. 

"Claude Opus 4 is the world’s best coding model, with sustained performance on complex, long-running tasks and agent workflows. Claude Sonnet 4 is a significant upgrade to Claude Sonnet 3.7, delivering superior coding and reasoning while responding more precisely to your instructions," the startup said in a[ blog post](https://www.anthropic.com/news/claude-4?ref=theleftshift.com). 

Claude Opus 4 currently leads in coding benchmarks, scoring 72.5% on SWE-bench and 43.2% on Terminal-bench. It excels in long-running, complex tasks, outperforming all Sonnet models and significantly advancing the capabilities of AI agents in coding and problem-solving applications.

It claims that Claude Opus 4 is the world’s best coding model, capable of working autonomously for up to seven hours—nearly a full corporate workday.

![](https://storage.ghost.io/c/fd/78/fd78b498-7373-46b7-884c-46f69e81b24d/content/images/2025/05/Claude-4.webp)

**(Image-Anthropic)*

These new models aim to advance AI reasoning capabilities while delivering faster responses. 

Like others in the AI space, Anthropic has shifted toward "reasoning" models that solve complex problems step-by-step for better accuracy. While effective, such models often respond slowly—sometimes taking minutes to reply.

With the Claude 4.0 series, Anthropic claims to offer similar high-quality reasoning with improved speed.