Anthropic

Anthropic: Claude Opus 4.6 Fast

anthropic/claude-opus-4.6-fast

Access Claude Opus 4.6 Fast 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-4.6-fast"
}).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-4.6-fast"
        }).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-4.6-fast",
    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-4.6-fast",
    "messages": [
      {"role": "user", "content": "Explain quantum computing in simple terms"}
    ]
  }'

Model Card

Claude Opus 4.6 Fast is a high-speed configuration of Anthropic's most intelligent model, delivering up to 2.5x faster output token generation with no reduction in quality or capabilities.

It runs the same Opus 4.6 model — state-of-the-art on benchmarks like Terminal-Bench 2.0 for agentic coding, Humanity's Last Exam for multidisciplinary reasoning, and GDPval-AA for professional knowledge work — but optimized for lower latency at premium pricing ($30/$150 per MTok). It supports the full 1M token context window and 128k max output tokens.

Fast mode is ideal for latency-sensitive, interactive workflows such as rapid iteration, live debugging, and real-time agentic tasks where waiting on responses breaks your flow. For cost-sensitive or batch workloads, standard Opus 4.6 offers the same intelligence at lower cost.

Context Window 1M

tokens

Max Output 128K

tokens

Input Cost $30

per million tokens

Output Cost $150

per million tokens

Release Date Apr 7, 2026

 

Model Playground

Try Claude Opus 4.6 Fast instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.

Chat anthropic/claude-opus-4.6-fast
Anthropic
Chat with Claude Opus 4.6 Fast
Powered by Puter.js

More AI Models From Anthropic

Chat

Claude Opus 4.7

Claude Opus 4.7 is Anthropic's most capable generally available model, built for complex reasoning and agentic coding. It offers a step-change improvement in long-horizon agentic work over its predecessor, Opus 4.6, along with strong gains in knowledge work, vision, and file-system-based memory. The model supports a 1M-token context window, 128k max output tokens, and adaptive thinking. It introduces high-resolution image input (up to 2576px / 3.75MP), a new `xhigh` effort level for demanding coding tasks, and task budgets (beta) that let the model self-moderate token usage across an agentic loop. Priced at $5 / $25 per million input/output tokens. Best suited for developers building autonomous agents, multi-step coding workflows, and vision-heavy pipelines where reliability and depth of reasoning matter most.

Chat

Claude Sonnet 4.6

Claude Sonnet 4.6 is Anthropic's latest mid-tier model released February 2026, delivering near-flagship Opus-level performance in coding, computer use, and agentic tasks at a fraction of the cost ($3/$15 per million tokens). It features a 1M token context window in beta, scores 79.6% on SWE-bench Verified and 72.5% on OSWorld. Developers preferred it over both Sonnet 4.5 (~70% of the time) and even Opus 4.5 (~59%) in real-world coding tests.

Chat

Claude Opus 4.6

Claude Opus 4.6 is Anthropic's latest model, released February 2026. It is a powerful model for coding and agentic tasks, with a 200K token context window and a 64K output context window.

View all Anthropic models →

Frequently Asked Questions

How do I use Claude Opus 4.6 Fast?

You can access Claude Opus 4.6 Fast 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.

Is Claude Opus 4.6 Fast free?

Yes, it is free if you're using it through Puter.js. With the User-Pays Model, you can add Claude Opus 4.6 Fast to your app at no cost — your users pay for their own AI usage directly, making it completely free for you as a developer.

What is the pricing for Claude Opus 4.6 Fast?
Pricing for Claude Opus 4.6 Fast is based on the number of input and output tokens used per request.
Price per 1M tokens
Input$30
Output$150
Who created Claude Opus 4.6 Fast?

Claude Opus 4.6 Fast was created by Anthropic and released on Apr 7, 2026.

What is the context window of Claude Opus 4.6 Fast?

Claude Opus 4.6 Fast supports a context window of 1M tokens. For reference, that is roughly equivalent to 2,000 pages of text.

What is the max output length of Claude Opus 4.6 Fast?

Claude Opus 4.6 Fast can generate up to 128K tokens in a single response.

Does it work with React / Vue / Vanilla JS / Node / etc.?

Yes — the Claude Opus 4.6 Fast 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 4.6 Fast to your app without worrying about API keys or setup.

Read the Docs View Tutorials