# LLM.txt - Claude Sonnet 4.6: Opus-Level Intelligence at Sonnet Price ## Article Metadata - **Title**: Claude Sonnet 4.6: Opus-Level Intelligence at Sonnet Price - **URL**: https://www.llmrumors.com/news/claude-sonnet-46-opus-level-intelligence-sonnet-price - **Publication Date**: February 18, 2026 - **Reading Time**: 13 min read - **Tags**: Claude Sonnet 4.6, Anthropic, Computer Use, AI Coding, Claude Code, Context Window, Agentic AI - **Slug**: claude-sonnet-46-opus-level-intelligence-sonnet-price ## Summary Claude Sonnet 4.6 is the new claude.ai default - preferred over Opus 4.5 59% of the time, with 1M context and $3/$15 per million tokens. ## Key Topics - Claude Sonnet 4.6 - Anthropic - Computer Use - AI Coding - Claude Code - Context Window - Agentic AI ## Content Structure This article from LLM Rumors covers: - Technical implementation details - Legal analysis and implications - Industry comparison and competitive analysis - Financial analysis and cost breakdown - Human oversight and quality control processes - Comprehensive source documentation and references ## Full Content Preview TL;DR: Claude Sonnet 4.6, released February 17, 2026, is now the default model on claude.ai and Claude Cowork - and it just made Opus-class performance available at Sonnet pricing. Users in early access preferred Sonnet 4.6 over Sonnet 4.5 70% of the time and over Opus 4.5 59% of the time[1]. It ships with a 1M token context window in beta, leads all Sonnet models on OSWorld computer use, and developed a novel business strategy on Vending-Bench Arena that no prior model had tried. Pricing stays flat at $3/$15 per million tokens. This is the biggest gap between capability and price that Anthropic has ever released. There's a story Anthropic has been telling for two years: that intelligence should cascade down the model family, not stay locked at the frontier tier. Every Sonnet release is a test of whether that story is true. Claude Sonnet 4.6 is the first time it feels genuinely proven. Twelve days ago, Opus 4.6 launched as the most capable model in Anthropic's history - the model that dethroned incumbents on agentic benchmarks, rewrote enterprise market share numbers, and commanded $5/$25 per million tokens as the price of admission. Today, Sonnet 4.6 does a significant portion of what Opus does, at 60% less cost, and it's now free for every user on every plan. That's not a product update. That's a statement about where the frontier actually lives. Sonnet 4.6 is now the default model across all Claude plans, Claude Cowork, Claude Code, and the API - including the free tier. Anthropic upgraded free users to Sonnet 4.6 and added file creation, connectors, skills, and compaction to that tier simultaneously[1]. The gap between "free Claude" and "Claude that matters" just got a lot smaller. The Preference Numbers That Should Worry Anthropic's Pricing Team Anthropic ran head-to-head preference evaluations in Claude Code - one of the most demanding real-world environments for a model, where errors compound over long sessions and instruction following is tested repeatedly across a single context. The results are stark. A 59% preference rate over Opus 4.5 means that for a majority of coding tasks, users actively chose the cheaper model when given both options blind. This isn't just a benchmark win. It's users voting with their attention on real work. The specific complaints about Sonnet 4.5 that Sonnet 4.6 addresses are worth reading closely: overengineering, laziness, false claims of task completion, hallucinations in long sessions, poor instruction following on multi-step tasks[1]. These aren't edge case failures. They're the core failure modes of every LLM that gets deployed in production. Sonnet 4.6 apparently fixed most of them. At Sonnet pricing. "Performance that would have previously required reaching for an Opus-class model is now available with Sonnet 4.6." Anthropic, February 17, 2026 Computer Use: From Experimental to Actually Useful In October 2024, Anthropic launched computer use and called it "still experimental - at times cumbersome and error-prone." That was honest. It was also a 16-month countdown to what Sonnet 4.6 delivers today. The OSWorld benchmark tests models on real software - Chrome, LibreOffice, VS Code, and more - running on a simulated computer. No special APIs. No purpose-built connectors. The model sees a screen and interacts with it the way a person would: clicking a mouse, typing on a keyboard. The practical milestone isn't the benchmark number - it's the report from early users. They're seeing human-level capability on tasks like navigating complex spreadsheets and filling out multi-step web forms across multiple browser tabs[1]. That's the inflection point. Not "better than before." Human-level on specific, economically valuable categories of tasks. The prompt injection improvement is equally significant. Malicious content embedded in webpages - the core attack ve... [Content continues - full article available at source URL] ## Citation Format **APA Style**: LLM Rumors. (2026). Claude Sonnet 4.6: Opus-Level Intelligence at Sonnet Price. Retrieved from https://www.llmrumors.com/news/claude-sonnet-46-opus-level-intelligence-sonnet-price **Chicago Style**: LLM Rumors. "Claude Sonnet 4.6: Opus-Level Intelligence at Sonnet Price." Accessed February 20, 2026. https://www.llmrumors.com/news/claude-sonnet-46-opus-level-intelligence-sonnet-price. ## Machine-Readable Tags #LLMRumors #AI #Technology #ClaudeSonnet4.6 #Anthropic #ComputerUse #AICoding #ClaudeCode #ContextWindow #AgenticAI ## Content Analysis - **Word Count**: ~1,489 - **Article Type**: News Analysis - **Source Reliability**: High (Original Reporting) - **Technical Depth**: Medium - **Target Audience**: AI Professionals, Researchers, Industry Observers ## Related Context This article is part of LLM Rumors' coverage of AI industry developments, focusing on data practices, legal implications, and technological advances in large language models. --- Generated automatically for LLM consumption Last updated: 2026-02-20T00:25:55.241Z Source: LLM Rumors (https://www.llmrumors.com/news/claude-sonnet-46-opus-level-intelligence-sonnet-price)