# Puppeteer
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###### [API](https://github.com/puppeteer/puppeteer/blob/v10.4.0/docs/api.md) | [FAQ](#faq) | [Contributing](https://github.com/puppeteer/puppeteer/blob/main/CONTRIBUTING.md) | [Troubleshooting](https://github.com/puppeteer/puppeteer/blob/main/docs/troubleshooting.md)
> Puppeteer is a Node library which provides a high-level API to control Chrome or Chromium over the [DevTools Protocol](https://chromedevtools.github.io/devtools-protocol/). Puppeteer runs [headless](https://developers.google.com/web/updates/2017/04/headless-chrome) by default, but can be configured to run full (non-headless) Chrome or Chromium.
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###### What can I do?
Most things that you can do manually in the browser can be done using Puppeteer! Here are a few examples to get you started:
- Generate screenshots and PDFs of pages.
- Crawl a SPA (Single-Page Application) and generate pre-rendered content (i.e. "SSR" (Server-Side Rendering)).
- Automate form submission, UI testing, keyboard input, etc.
- Create an up-to-date, automated testing environment. Run your tests directly in the latest version of Chrome using the latest JavaScript and browser features.
- Capture a [timeline trace](https://developers.google.com/web/tools/chrome-devtools/evaluate-performance/reference) of your site to help diagnose performance issues.
- Test Chrome Extensions.
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Give it a spin: [https://try-puppeteer.appspot.com/](https://try-puppeteer.appspot.com/)
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## Getting Started
### Installation
To use Puppeteer in your project, run:
```bash
npm i puppeteer
# or "yarn add puppeteer"
```
Note: When you install Puppeteer, it downloads a recent version of Chromium (~170MB Mac, ~282MB Linux, ~280MB Win) that is guaranteed to work with the API. To skip the download, download into another path, or download a different browser, see [Environment variables](https://github.com/puppeteer/puppeteer/blob/v10.4.0/docs/api.md#environment-variables).
### puppeteer-core
Since version 1.7.0 we publish the [`puppeteer-core`](https://www.npmjs.com/package/puppeteer-core) package,
a version of Puppeteer that doesn't download any browser by default.
```bash
npm i puppeteer-core
# or "yarn add puppeteer-core"
```
`puppeteer-core` is intended to be a lightweight version of Puppeteer for launching an existing browser installation or for connecting to a remote one. Be sure that the version of puppeteer-core you install is compatible with the
browser you intend to connect to.
See [puppeteer vs puppeteer-core](https://github.com/puppeteer/puppeteer/blob/main/docs/api.md#puppeteer-vs-puppeteer-core).
### Usage
Puppeteer follows the latest [maintenance LTS](https://github.com/nodejs/Release#release-schedule) version of Node.
Note: Prior to v1.18.1, Puppeteer required at least Node v6.4.0. Versions from v1.18.1 to v2.1.0 rely on
Node 8.9.0+. Starting from v3.0.0 Puppeteer starts to rely on Node 10.18.1+. All examples below use async/await which is only supported in Node v7.6.0 or greater.
Puppeteer will be familiar to people using other browser testing frameworks. You create an instance
of `Browser`, open pages, and then manipulate them with [Puppeteer's API](https://github.com/puppeteer/puppeteer/blob/v10.4.0/docs/api.md#).
**Example** - navigating to https://example.com and saving a screenshot as _example.png_:
Save file as **example.js**
```js
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://example.com');
await page.screenshot({ path: 'example.png' });
await browser.close();
})();
```
Execute script on the command line
```bash
node example.js
```
Puppeteer sets an initial page size to 800×600px, which defines the screenshot size. The page size can be customized with [`Page.setViewport()`](https://github.com/puppeteer/puppeteer/blob/v10.4.0/docs/api.md#pagesetviewportviewport).
**Example** - create a PDF.
Save file as **hn.js**
```js
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://news.ycombinator.com', {
waitUntil: 'networkidle2',
});
await page.pdf({ path: 'hn.pdf', format: 'a4' });
await browser.close();
})();
```
Execute script on the command line
```bash
node hn.js
```
See [`Page.pdf()`](https://github.com/puppeteer/puppeteer/blob/v10.4.0/docs/api.md#pagepdfoptions) for more information about creating pdfs.
**Example** - evaluate script in the context of the page
Save file as **get-dimensions.js**
```js
const puppeteer = require('puppeteer');
(async () => {
const browser = await puppeteer.launch();
const page = await browser.newPage();
await page.goto('https://example.com');
// Get the "viewport" of the page, as reported by the page.
const dimensions = await page.evaluate(() => {
return {
width: document.documentElement.clientWidth,
height: document.documentElement.clientHeight,
deviceScaleFactor: window.devicePixelRatio,
};
});
console.log('Dimensions:', dimensions);
await browser.close();
})();
```
Execute script on the command line
```bash
node get-dimensions.js
```
See [`Page.evaluate()`](https://github.com/puppeteer/puppeteer/blob/v10.4.0/docs/api.md#pageevaluatepagefunction-args) for more information on `evaluate` and related methods like `evaluateOnNewDocument` and `exposeFunction`.
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## Default runtime settings
**1. Uses Headless mode**
Puppeteer launches Chromium in [headless mode](https://developers.google.com/web/updates/2017/04/headless-chrome). To launch a full version of Chromium, set the [`headless` option](https://github.com/puppeteer/puppeteer/blob/v10.4.0/docs/api.md#puppeteerlaunchoptions) when launching a browser:
```js
const browser = await puppeteer.launch({ headless: false }); // default is true
```
**2. Runs a bundled version of Chromium**
By default, Puppeteer downloads and uses a specific version of Chromium so its API
is guaranteed to work out of the box. To use Puppeteer with a different version of Chrome or Chromium,
pass in the executable's path when creating a `Browser` instance:
```js
const browser = await puppeteer.launch({ executablePath: '/path/to/Chrome' });
```
You can also use Puppeteer with Firefox Nightly (experimental support). See [`Puppeteer.launch()`](https://github.com/puppeteer/puppeteer/blob/v10.4.0/docs/api.md#puppeteerlaunchoptions) for more information.
See [`this article`](https://www.howtogeek.com/202825/what%E2%80%99s-the-difference-between-chromium-and-chrome/) for a description of the differences between Chromium and Chrome. [`This article`](https://chromium.googlesource.com/chromium/src/+/refs/heads/main/docs/chromium_browser_vs_google_chrome.md) describes some differences for Linux users.
**3. Creates a fresh user profile**
Puppeteer creates its own browser user profile which it **cleans up on every run**.
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## Resources
- [API Documentation](https://github.com/puppeteer/puppeteer/blob/v10.4.0/docs/api.md)
- [Examples](https://github.com/puppeteer/puppeteer/tree/main/examples/)
- [Community list of Puppeteer resources](https://github.com/transitive-bullshit/awesome-puppeteer)
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## Debugging tips
1. Turn off headless mode - sometimes it's useful to see what the browser is
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