Anthropic · Claude 4

Claude Sonnet 4.6

The pragmatic default — Claude quality without Opus pricing.

Claude Sonnet 4.6 is a large language model developed by Anthropic as part of the Claude 4 family. It is designed for versatile applications in text and image processing, featuring a massive 1,000,000 token context window that enables deep context awareness and long-form content generation. This multimodal capability allows it to perform tasks involving both textual and visual data with high accuracy and reliability.

Technically, the model integrates advanced architecture and attention mechanisms to handle complex text relationships effectively, ensuring coherence and reducing hallucination rates in extended tasks. It is fine-tuned for safety alignment and robust performance, making it an ideal tool for complex, high-context workflows.

Claude Sonnet 4.6 represents a flagship advancement in the Claude 4 lineup, introducing one of the largest context windows in the industry and refined multimodal capabilities. Compared to its predecessors, it offers improved coherence, data handling, and safety alignment, making it more suited for modern, large-scale applications.

Background

Claude is a series of large language models developed by Anthropic and first released in 2023. Since Claude 3, each generation has typically been released in three sizes, from least to most capable: Haiku, Sonnet, and Opus. An additional model named Claude Mythos was released to some companies in 2026 but not to the public.

Wikipedia

Specs

Context window: 1M tokens
Max output: 128K tokens
Input ($/1M tokens): $3.00
Output ($/1M tokens): $15.00
Modalities: Text · Image
Weights: Closed

Pricing last synced Apr 27, 2026 via OpenRouter. Confirm against official docs before committing.

Capabilities

Tool use
Vision
Extended thinking
Prompt caching
Open weights

What it excels at

Large context window
Processes up to 1,000,000 tokens for extensive context handling.
Multimodal capabilities
Supports both text and image inputs for versatile applications.
Improved coherence
Maintains contextual relevance in long-form and detailed tasks.
Safety alignment
Reduces the likelihood of producing harmful or misleading outputs.
Nuanced comprehension
Delivers precise and relevant responses with advanced text analysis.

When to use this model

→Document summarization — Handles extended texts with its large context window.
→Multimodal content creation — Generates outputs combining text and image inputs seamlessly.
→Complex query answering — Leverages deep context to deliver detailed and accurate answers.
→Educational support — Provides detailed explanations over long interactions.
→Enterprise knowledge management — Processes and contextualizes large datasets efficiently.

Analysis synthesized from gpt-4o, llama-4-maverick, phi-4, etc.

Recent coverage

What people are saying

Tell HN: Anthropic no longer allows you to fix to specific model version

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Show HN: Keep large tool output out of LLM context: 3x accuracy 95% fewer tokens

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API model id

claude-sonnet-4-6

Vendor docs: docs.anthropic.com

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