Claude Sonnet 5.5

Approved Data Classifications

This model is only approved for Open Data. When leveraging NaviGator AI’s suite offerings, please ensure you are selecting models that meet the compliance requirements in accordance with UF’s Data Classifications, grant awards or project specifications, and state and federal law.

Description

Claude Sonnet 5.5 is Anthropic’s latest Sonnet model and the second model in the Claude 5.5 family. It is a direct upgrade over Claude Sonnet 5, running over 30% faster while costing up to 30% less for most work at the same per-token price. Sonnet 5.5 is strongest at well-scoped everyday tasks, fixing bugs, and producing polished documents, slides, and spreadsheets, and on several evaluations it approaches Claude Opus 5.5. It retains a 1-million-token context window with up to 128K-token outputs, and adaptive thinking is enabled by default.

Capabilities

Model	Knowledge Cutoff	Input	Output	Context Length	Cost (per 1 million tokens)
claude-sonnet-5.5	Jun 2026	Text, Image, Pdf	Text	1,000,000	$2.20/1M input $11.00/1M output

info

• 1M represents 1 Million Tokens
• All prices listed are based on 1 Million Tokens
• Maximum output: 128,000 tokens
• Cache reads: $0.11 per 1M tokens
• Cache writes: $2.75 per 1M tokens

Availability

Cloud Provider

Usage

curl

curl -X POST https://api.ai.it.ufl.edu/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer <API_TOKEN>" \
-d '{
    "model": "claude-sonnet-5.5",
    "messages": [
        {
            "role": "system",
            "content": "You are a helpful assistant."
        },
        {
            "role": "user",
            "content": "Write a haiku about an Alligator."
        }
    ]
}'

python

from openai import OpenAI

client = OpenAI(
    api_key="your_api_key",
    base_url="https://api.ai.it.ufl.edu/v1"
)

response = client.chat.completions.create(
    model="claude-sonnet-5.5", # model to send to the proxy
    messages = [
        { "role": "system", "content": "You are a helpful assistant." },
        {
            "role": "user",
            "content": "Write a haiku about an Alligator."
        }
    ]
)

print(response.choices[0].message)

javascript

import OpenAI from 'openai';

const openai = new OpenAI({
  apiKey: 'your_api_key',
  baseURL: 'https://api.ai.it.ufl.edu/v1'
});

const completion = await openai.chat.completions.create({
    model: "claude-sonnet-5.5",
    messages: [
        { role: "system", content: "You are a helpful assistant." },
        {
            role: "user",
            content: "Write a haiku about an Alligator.",
        },
    ],
});

console.log(completion.choices[0].message)

When to use

• Everyday coding — fixing bugs, well-scoped changes, and iterating quickly on a known codebase
• Document and knowledge work — producing polished documents, slides, and spreadsheets
• AI agents and automation — multi-step tool use where speed and cost per task matter
• Computer/browser use — workflows that interact with websites or desktop applications
• High-volume production workloads — when you want near-Opus quality at Sonnet cost and latency

tip

Adaptive thinking is enabled by default on Claude Sonnet 5.5, including for requests that omit the thinking field. Setting temperature, top_p, or top_k to a non-default value returns a 400 error.

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References

1. Anthropic - Introducing Claude Sonnet 5.5
   https://www.anthropic.com/claude-sonnet-5-5
2. Claude Platform Docs - Claude Sonnet 5.5
   https://platform.claude.com/docs/en/models/sonnet-5-5/overview
3. Claude Platform Docs - What's new in Claude Sonnet 5.5
   https://platform.claude.com/docs/en/models/sonnet-5-5/whats-new-sonnet-5-5
4. Claude Platform Docs - Pricing
   https://platform.claude.com/docs/en/about-claude/pricing
5. Artificial Analysis
   https://artificialanalysis.ai/models/claude-sonnet-5-5