Story perspectives

Anthropic Launches Claude Sonnet 4.6: Enhanced Reasoning & Data Tools

2/18/2026

Summary

Story summary

Anthropic released Claude Sonnet 4.6, the default model for Free and Pro users.
The model features a 1 million token context window for processing entire codebases and documents.
Early evaluations show strong performance in complex reasoning tasks, with 77% accuracy in deep reasoning tests, up 15 percentage points from Claude Sonnet 4.5.
The model outperformed Opus 4.5 in benchmarks.
It also includes MCP connectors for Excel to enable data interaction.

History

Historical Context

Anthropic, founded in 2021 by former OpenAI employees, launched Claude Sonnet 4.6 in 2023, featuring a 1 million token context window and achieving 77% accuracy in deep reasoning tests. This advancement follows the 2012 introduction of deep learning techniques by Geoffrey Hinton, marking a significant evolution in AI capabilities and its integration into tools like Excel for enhanced data processing.

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Story summary

Anthropic released Claude Sonnet 4.6, the default model for Free and Pro users.
The model features a 1 million token context window for processing entire codebases and documents.
Early evaluations show strong performance in complex reasoning tasks, with 77% accuracy in deep reasoning tests, up 15 percentage points from Claude Sonnet 4.5.
The model outperformed Opus 4.5 in benchmarks.
It also includes MCP connectors for Excel to enable data interaction.

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