Anthropic: Claude Opus 4.1
anthropic/claude-opus-4-1
Access Claude Opus 4.1 from Anthropic using Puter.js AI API.
Get Started// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';
puter.ai.chat("Explain quantum computing in simple terms", {
model: "anthropic/claude-opus-4-1"
}).then(response => {
document.body.innerHTML = response.message.content;
});
<html>
<body>
<script src="https://js.puter.com/v2/"></script>
<script>
puter.ai.chat("Explain quantum computing in simple terms", {
model: "anthropic/claude-opus-4-1"
}).then(response => {
document.body.innerHTML = response.message.content;
});
</script>
</body>
</html>
# pip install openai
from openai import OpenAI
client = OpenAI(
base_url="https://api.puter.com/puterai/openai/v1/",
api_key="YOUR_PUTER_AUTH_TOKEN",
)
response = client.chat.completions.create(
model="anthropic/claude-opus-4-1",
messages=[
{"role": "user", "content": "Explain quantum computing in simple terms"}
],
)
print(response.choices[0].message.content)
curl https://api.puter.com/puterai/openai/v1/chat/completions \
-H "Content-Type: application/json" \
-H "Authorization: Bearer YOUR_PUTER_AUTH_TOKEN" \
-d '{
"model": "anthropic/claude-opus-4-1",
"messages": [
{"role": "user", "content": "Explain quantum computing in simple terms"}
]
}'
Model Card
Claude Opus 4.1 is an August 2025 incremental upgrade to Opus 4 focused on agentic tasks and real-world coding. It improved coding accuracy to 74.5% on SWE-bench with finer-grained refactoring and more precise bug fixes.
Context Window 200K
tokens
Max Output 32K
tokens
Input Cost $15
per million tokens
Output Cost $75
per million tokens
Input text, image, pdf
modalities
Tool Use Yes
Knowledge Cutoff Mar 31, 2025
Release Date Aug 5, 2025
Output Speed 36
tokens / sec
Latency 1.87s
time to first token
Model Playground
Try Claude Opus 4.1 instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.
Benchmarks
How Claude Opus 4.1 performs on standard evaluations.
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Frequently Asked Questions
You can access Claude Opus 4.1 by Anthropic through Puter.js AI API. Include the library in your web app or Node.js project and start making calls with just a few lines of JavaScript — no backend and no configuration required. You can also use it with Python or cURL via Puter's OpenAI-compatible API.
Yes, it is free if you're using it through Puter.js. With the User-Pays Model, you can add Claude Opus 4.1 to your app at no cost — your users pay for their own AI usage directly, making it completely free for you as a developer.
| Price per 1M tokens | |
|---|---|
| Input | $15 |
| Output | $75 |
Claude Opus 4.1 was created by Anthropic and released on Aug 5, 2025.
Claude Opus 4.1 supports a context window of 200K tokens. For reference, that is roughly equivalent to 400 pages of text.
Claude Opus 4.1 can generate up to 32K tokens in a single response.
Claude Opus 4.1 has a knowledge cutoff date of Mar 31, 2025. This means the model was trained on data available up to that date.
Claude Opus 4.1 accepts the following input types: text, image, pdf. It produces: text.
Yes, Claude Opus 4.1 supports tool use (function calling), allowing it to interact with external tools, APIs, and data sources as part of its response flow.
Claude Opus 4.1 scores 28.2 on the Artificial Analysis Intelligence Index, outperforming 73% of tracked models.
Yes — the Claude Opus 4.1 API works with any JavaScript framework, Node.js, or plain HTML through Puter.js. Just include the library and start building. See the documentation for more details.
Get started with Puter.js
Add Claude Opus 4.1 to your app without worrying about API keys or setup.
Read the Docs View Tutorials