Claude Sonnet 5.5

Name: Claude Sonnet 5.5
Price: 2 USD
Author: Anthropic

Claude Sonnetv5.5Current

Anthropic(ai lab)

Released September 28, 2026

API Docs Playground

Context1M tokens

Price (In / Out)$2.00/M / $10.00/M

Training Cutoff2026-06

CategoryLarge Language Model

Max Output128K tokens

About Claude Sonnet 5.5

Claude Sonnet 5.5 is Anthropic's proprietary adaptive-reasoning model. The Claude API identifier is claude-sonnet-5-5. It accepts text and images, returns text, has a 1,000,000-token context window and a 128,000-token standard output limit. Anthropic lists standard API input and output pricing at $2 and $10 per million tokens.

Capabilities

textvisionreasoningcodingtool uselong contextcontext caching

Input Modalities

textimage

Output Modalities

text

Technical Details

API Identifier: claude-sonnet-5-5
Category: Large Language Model
Context Window: 1,000,000 tokens
Max Output Tokens: 128,000 tokens

Benchmarks

Performance scores for Claude Sonnet 5.5 across standard benchmarks.

Artificial Analysis Intelligence Index v4.3.2Artificial Analysis

56 index

Pricing

Token pricing for Claude Sonnet 5.5 API usage.

Input Tokens

$2.00/M

per million tokens

Output Tokens

$10.00/M

per million tokens

Anthropic Claude API standard tier, USD per million tokens: $2 input, $10 output; 5-minute cache writes $2.50, 1-hour cache writes $4, cache reads $0.20. Batch API gives 50% off input and output. A 300K output limit is available only for Message Batches API with the output-300k-2026-03-24 beta header; standard maximum output is 128K. Provider and regional terms may vary.

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Building reliable, interpretable, and steerable AI systems

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Claude Fable 5.1Current	1.0M	$10.00 / $50.00	textvisionreasoningcoding+4
Claude Opus 5Current	1.0M	$5.00 / $25.00	textvisionreasoningcoding+3
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Claude Opus 4.7Current	1.0M	$5.00 / $25.00	textvisioncodetool use
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