Claude Sonnet 5.5

Claude Sonnet 5.5: 30%+ faster than Sonnet 5, with 1M-token context.

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Anthropic's fast, cost-efficient AI model for everyday coding, documents and design work.

Claude Sonnet 5.5 announcement

Claude Sonnet 5.5 announcement

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Overview

What is Claude Sonnet 5.5?

Claude Sonnet 5.5: 30%+ faster than Sonnet 5, with 1M-token context.

Claude Sonnet 5.5 is Anthropic's fast, cost-efficient AI model for everyday work — coding, bug fixes, documents, slides, spreadsheets and design. The second model in the Claude 5.5 family, it runs 30%+ faster than Sonnet 5 and costs up to 30% less per task, with a 1M-token context window.

Benchmarks (official): Terminal-Bench 4.0 agentic coding at 70.6% (vs 10.3% for Sonnet 5, ahead of Opus 5.5's 66.4%); GDPval-AA knowledge work at 1844; OSWorld computer use 80.1%. It follows slide templates to produce decks needing minimal editing, has adjustable effort levels for cost/speed/quality tradeoffs, and is the first Sonnet with Opus-class cyber safeguards.

Access it through Claude web/desktop/mobile apps, the Claude API (model ID claude-sonnet-5-5), Claude Code, Claude in Chrome and Microsoft 365, AWS Bedrock, Google Cloud, Microsoft Azure, and GitHub Copilot (GA).

Pricing: API at $2 per 1M input tokens and $10 per 1M output tokens, with prompt cache reads at $0.20/1M and writes at $2.50/1M. Claude app plans: Free $0; Pro $17/mo billed annually or $20/mo monthly; Max from $100/mo; Enterprise $20/seat/mo plus API usage.

Platforms and languages

Claude Sonnet 5.5 Availability

Platforms

WebApi

Languages

English

Capabilities

Claude Sonnet 5.5 Key Features

Fastest Sonnet to date

30%+ faster output generation than Sonnet 5, lowering task costs up to 30%.

1M-token context

1M-token context window for large codebases and long documents.

Strong coding and knowledge-work benchmarks

Terminal-Bench 4.0 at 70.6%, CursorBench 55.5%, GDPval-AA knowledge work at 1844 — near Opus 5.5 at Sonnet cost.

Design and slide generation

Follows slide templates to produce decks needing minimal editing, with a sharp eye for design.

Adjustable effort levels

Adjustable effort levels let you trade off cost, speed and quality per task.

Enterprise-grade safeguards

First Sonnet with Opus-class cyber safeguards, fallback protections and anti-distillation safety classifiers; zero data retention available on Claude Platform, AWS, Google Cloud and Azure.

Best for

Who uses Claude Sonnet 5.5?

Developers and enterprises

Coding, bug fixes and agentic development with a fast, cost-efficient model

Knowledge workers and teams

Documents, slides, spreadsheets and design tasks on Claude apps or the API

Plans and access

Claude Sonnet 5.5 Pricing

Freemium

API $2 in / $10 out per 1M tokens. App: Free $0, Pro $17-$20/mo, Max from $100, Enterprise $20/seat.

No free trial listed
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Common questions

Claude Sonnet 5.5 FAQs

What is Claude Sonnet 5.5?

It's Anthropic's fast, cost-efficient AI model for everyday work — coding, bug fixes, documents, slides and design. It runs 30%+ faster than Sonnet 5, costs up to 30% less per task, and has a 1M-token context window.

How much does the Claude Sonnet 5.5 API cost?

Official pricing is $2 per 1M input tokens and $10 per 1M output tokens, with prompt caching at $0.20/1M for reads and $2.50/1M for writes. Claude app plans run from Free ($0) to Pro ($17-$20/mo), Max (from $100/mo) and Enterprise ($20/seat/mo + API usage).

How can I access Claude Sonnet 5.5?

Through the Claude web, desktop and mobile apps, the Claude API (model ID claude-sonnet-5-5), Claude Code, Claude in Chrome and Microsoft 365, AWS Bedrock, Google Cloud, Microsoft Azure, and GitHub Copilot.

How does Sonnet 5.5 compare to Sonnet 5?

Per Anthropic's benchmarks, it's 30%+ faster at generating output and much stronger on agentic coding (Terminal-Bench 4.0: 70.6% vs 10.3%) and knowledge work, at up to 30% lower task cost.

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