Anthropic: Claude Sonnet 5
anthropic/claude-sonnet-5
Try Claude Sonnet 5 for free in your browser, and add it to your app for free with Puter.js AI API.
Try it free Add to your app// npm install @heyputer/puter.js
import { puter } from '@heyputer/puter.js';
puter.ai.chat("Explain quantum computing in simple terms", {
model: "anthropic/claude-sonnet-5"
}).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-sonnet-5"
}).then(response => {
document.body.innerHTML = response.message.content;
});
</script>
</body>
</html>
Model Card
Claude Sonnet 5 is Anthropic's newest Sonnet-tier model, released June 30, 2026 as the successor to Sonnet 4.6. Anthropic built it to be the most agentic Sonnet yet, with gains in planning, tool use, coding, and multi-step reasoning that bring it close to Opus 4.8 quality at a lower price.
On SWE-bench Pro it scores 63.2%, up from Sonnet 4.6's 58.1% and ahead of GPT-5.5's 58.6%, though still behind Opus 4.8's 69.2%. On Terminal-Bench 2.1 it reaches 80.4% versus Sonnet 4.6's 67.0%, and on the OSWorld-Verified computer-use benchmark it posts 81.2% against Sonnet 4.6's 78.5%.
It targets developers running agentic coding pipelines, automation workflows, and tool-heavy tasks who want most of Opus-tier capability without Opus pricing. It launched at $2/$10 per million input/output tokens as introductory pricing through August 31, 2026, and that price has continued as the standard rate. Max output tokens increased from 64,000 to 128,000 after launch.
Context Window 1M
tokens
Max Output 128K
tokens
Input Cost $2
per million tokens
Output Cost $10
per million tokens
Input text, image, pdf
modalities
Tool Use Yes
Knowledge Cutoff Jan 2026
Release Date Jun 30, 2026
Output Speed 79
tokens / sec
Latency 175.45s
time to first token
Try Claude Sonnet 5 for free
Try Claude Sonnet 5 instantly in your browser.
This playground uses the Puter.js AI API — no API keys or setup required.
Benchmarks
How Claude Sonnet 5 performs on standard evaluations.
| Benchmark | Score |
|---|---|
| GPQA Diamond Graduate-level science Q&A | 91.1% |
| Humanity's Last Exam Cross-domain reasoning | 41.3% |
| SciCode Scientific programming | 54.3% |
| LCR Long-context reasoning | 82.0% |
Scores sourced from Artificial Analysis.
Find other Anthropic models →
Claude Fable 5.2
Claude Fable 5.2 is Anthropic's update to Claude Fable 5.1, released on November 9, 2026. It is the publicly available model of a pair, alongside Claude Mythos 5.2, which has looser cybersecurity and biology safeguards and is limited to vetted organizations. Anthropic says it produces output up to 30% faster than the 5.1 versions. Anthropic reports 49.1% on FrontierCode 2.0 (Fable 5.1: 32.4%), 74.6% on Terminal-Bench-Science 0.1 (52.6%), and 89.3% on OSWorld 2.1 (83.5%). Pricing is $8 per million input tokens and $40 per million output tokens, down from $10 and $50 for Fable 5.1. It targets large, loosely defined coding tasks, multi-day agent work, and scientific research. Anthropic recommends Opus 5.5 for most coding and knowledge tasks.
ChatClaude Haiku 5.5
Claude Haiku 5.5 is the small, low-cost model in Anthropic's 5.5 family, released on October 7, 2026 and available through the API as anthropic/claude-haiku-5-5. It has a 1M token context window and up to 128k output tokens. Pricing is $0.10 per million input tokens and $0.50 per million output tokens for requests under 100,000 tokens, down from $1 and $5 for Haiku 4.5, and $0.50 and $2.50 above that. Effort levels range from low to max, with medium as the default. Anthropic reports 72.4% on OSWorld 2.1 (offline subset, Haiku 4.5: 15.7%) and 39.2% on Terminal-Bench 4.0 at maximum effort (Haiku 4.5: 0.0%). On the same tests GPT-6 Luna scores 48.9% and 16.4%. It is aimed at summarizing documents, classifying information, querying databases, and handling subtasks for larger agents. Anthropic recommends Opus and Sonnet for demanding coding work.
ChatClaude Sonnet 5.5
Claude Sonnet 5.5 is a mid-tier model from Anthropic, released on September 28, 2026 and available through the API as anthropic/claude-sonnet-5-5. It accepts text, image, and PDF input, with a 1M token context window and up to 128k output tokens. Pricing is $2 per million input tokens and $10 per million output tokens, the same as Claude Sonnet 5. Anthropic says it generates output more than 30% faster than Sonnet 5 and can cut the cost of a task by up to 30%, because it uses fewer tokens and fewer tool calls. Anthropic reports 70.6% on Terminal-Bench 4.0 (Sonnet 5: 10.3%) and 80.1% on OSWorld 2.1 (Sonnet 5: 57.0%). It is aimed at well-scoped everyday tasks, bug fixing, agentic coding, and producing documents, slides, and spreadsheets.
Frequently Asked Questions
You can access Claude Sonnet 5 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.
Claude Sonnet 5 is free to try with a Puter account. Every account includes a free AI allowance, and you can chat with it in the playground on this page. You can upgrade your account anytime for a larger allowance.
Claude Sonnet 5 is free to integrate using the Puter.js AI API. With the User-Pays Model, you can add AI to your app for $0, since users cover their own AI usage through their Puter account.
| Price per 1M tokens | |
|---|---|
| Input | $2 |
| Output | $10 |
Claude Sonnet 5 was created by Anthropic and released on Jun 30, 2026.
Claude Sonnet 5 supports a context window of 1M tokens. For reference, that is roughly equivalent to 2,000 pages of text.
Claude Sonnet 5 can generate up to 128K tokens in a single response.
Claude Sonnet 5 has a knowledge cutoff date of Jan 2026. This means the model was trained on data available up to that date.
Claude Sonnet 5 accepts the following input types: text, image, pdf. It produces: text.
Yes, Claude Sonnet 5 supports tool use (function calling), allowing it to interact with external tools, APIs, and data sources as part of its response flow.
Yes — the Claude Sonnet 5 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.
Add Claude Sonnet 5 to your app for free
Developers can integrate Claude Sonnet 5 for free using the Puter.js AI API.
With the User-Pays Model, each user covers their own AI usage instead of the developer.