Claude Sonnet 5.5Latest

The best combination of speed and intelligence

Context window: 1Mtokens
Max output: 128Ktokens
Input pricing: $2/ MTok
Output pricing: $10/ MTok

Overview

Claude Sonnet 5.5 offers the best combination of speed and intelligence. It’s built for everyday coding, agent, and enterprise workloads, such as code generation, data analysis, content creation, visual understanding, and agentic tool use.

How it compares

Model	Context	Max output	Price / MTok	Latency	Thinking	Default effort	Knowledge cutoff
Claude Fable 5.2	1M	128K	$8 / $40	Moderate	Adaptive (always on)	`high`	Jun 2026
Claude Opus 5.5	1M	128K	$4 / $20	Moderate	Adaptive (always on)	`medium`	Jun 2026
Claude Sonnet 5.5This model	1M	128K	$2 / $10	Fast	Adaptive	`high`	Jun 2026
Claude Haiku 5.5	1M	128K	From $0.10 / $0.50	Fastest	Adaptive	`medium`	Jun 2026

Specifications

Model IDs

Claude API
Amazon Bedrock
Claude Models on Google Cloud (Google managed)
Microsoft Foundry
Claude Platform on AWS
Claude Models on Google Cloud (Anthropic managed)

Pricing

Input: $2 / MTok
Output: $10 / MTok
5m cache write: $2.50 / MTok
1h cache write: $4 / MTok
Cache read: $0.10 / MTok
Batch API: 50% discount on input and output

Full price list

Capabilities

Context window: 1M tokens
Max output: 128K tokens
Max output (Batch API, beta): 300K tokens
Thinking: Adaptive
Default effort: high
Comparative latency: Fast
Input → output: Text and images → text
Reliable knowledge cutoff: Jun 2026
Training data cutoff: Jun 2026

Availability

Status: Active (latest)
Released: September 28, 2026
Retirement: Not sooner than September 28, 2027
Platforms: Claude APIAmazon Bedrock Claude Models on Google Cloud (Google managed)Microsoft Foundry Claude Platform on AWS Claude Models on Google Cloud (Anthropic managed)

Good to know

Adaptive thinking is on by default. The lowest thinking setting is between_tools, which turns off up-front thinking. It works at high effort or below. See What’s new in Claude Sonnet 5.5.
Setting temperature, top_p, or top_k returns a 400 error.
The minimum cacheable prompt length is 512 tokens. See Prompt caching.
On the Message Batches API, Claude Sonnet 5.5 supports up to 300k output tokens with the output-300k-2026-03-24 beta header.
Query limits and capabilities programmatically with the Models APIPreview with links to the API reference available — press Tab until focus enters the card, Escape to return..