Intelligence
Index v5.0
Custom pricing for production workloads

Anthropic's Sonnet-class model with 1M context and adaptive thinking
Claude Sonnet 5.5 is Anthropic's Sonnet-class model for well-scoped everyday work, succeeding Claude Sonnet 5 as a direct upgrade.
A large jump in agentic coding
Anthropic reports 70.6% on Terminal-Bench 4.0, against 10.3% for Claude Sonnet 5 on the same evaluation, and 55.5% on CursorBench 4.0 against 34.1%.
Computer use
80.1% on OSWorld 2.1 (partial credit), against 57.0% for Sonnet 5.
Agentic coding and long-running tasks
The Terminal-Bench and CursorBench gains over Sonnet 5 are the largest Anthropic reports for this release, and they are the tasks the model is aimed at.
Computer-use agents
80.1% on OSWorld 2.1 puts it within two points of Opus 5.5 at a lower price per token.
Claude Sonnet 5
The model this one replaces. Sonnet 5.5 is ahead on every benchmark Anthropic published for both, by wide margins on the agentic ones.
Claude Opus 5.5
The frontier tier. Opus leads on CursorBench 4.0 (57.8% vs 55.5%) and FrontierCode, ties on GDPval-AA (1846 vs 1844), and trails on Terminal-Bench 4.0 (66.4% vs 70.6%). Sonnet 5.5 is the cheaper choice where that gap does not matter.
See how Claude Sonnet 5.5 compares in intelligence, generation speed, cost per task and latency.
Compare 5 models available on AI/ML API across 4 independent benchmarks.
Expert-written questions across academic subjects.
Agentic tasks completed in a command-line environment.
Reasoning across long documents of about 100k tokens.
Python coding tasks drawn from scientific research.
| Usage | Price | Unit |
|---|---|---|
| Input | $2 | 1M tokens |
| Output | $10 | 1M tokens |
| Cached input | $0.2 | 1M tokens |
AI/ML API input and output rates for 5 models, per million tokens.
| Model | Input | Output |
|---|---|---|
| $2 | $10 | |
| $0.1 | $0.5 | |
| $4 | $20 | |
| $5 | $25 | |
| $10 | $50 |
Give your agent the model details, code and documentation.
export AIMLAPI_KEY="8f2b4c7d9a1e6b3f…"curl 'https://api.aimlapi.com/v1/chat/completions' \
-H "Authorization: Bearer $AIMLAPI_KEY" \
-H 'Content-Type: application/json' \
-d '{
"model": "anthropic/claude-sonnet-5.5",
"messages": [
{
"role": "user",
"content": "Write a haiku about the ocean."
}
]
}'import os
import requests
headers = {
"Authorization": f"Bearer {os.environ['AIMLAPI_KEY']}",
"Content-Type": "application/json",
}
payload = {
"model": "anthropic/claude-sonnet-5.5",
"messages": [
{
"role": "user",
"content": "Write a haiku about the ocean."
}
]
}
response = requests.post("https://api.aimlapi.com/v1/chat/completions", headers=headers, json=payload, timeout=120)
response.raise_for_status()
print(response.json())const response = await fetch("https://api.aimlapi.com/v1/chat/completions", {
method: "POST",
headers: {
Authorization: `Bearer ${process.env.AIMLAPI_KEY}`,
"Content-Type": "application/json",
},
body: JSON.stringify({
"model": "anthropic/claude-sonnet-5.5",
"messages": [
{
"role": "user",
"content": "Write a haiku about the ocean."
}
]
}),
});
if (!response.ok) throw new Error(`HTTP ${response.status}`);
console.log(await response.json());It is built for coding, agents, and professional work at scale. It is also described as suitable for reasoning, streaming, tools, and vision.
Anthropic positions it for coding, multi-step workflows and autonomous agents, and reports its largest gains over Claude Sonnet 5 on agentic evaluations such as Terminal-Bench 4.0 and CursorBench 4.0. The 1M-token context window also suits long documents and whole-repository work.
Yes. Anthropic says it is designed to navigate real codebases, land multi-file changes, and carry longer debugging and refactoring tasks through to completion.
Confirm that your workflow needs coding, agentic automation, tool use, or vision. The model is positioned for professional tasks at scale, so it is a strong fit when those capabilities matter most.