--- sidebar_label: BrowserFetcher --- # BrowserFetcher class BrowserFetcher can download and manage different versions of Chromium and Firefox. **Signature:** ```typescript export declare class BrowserFetcher ``` ## Remarks BrowserFetcher operates on revision strings that specify a precise version of Chromium, e.g. `"533271"`. Revision strings can be obtained from [omahaproxy.appspot.com](http://omahaproxy.appspot.com/). In the Firefox case, BrowserFetcher downloads Firefox Nightly and operates on version numbers such as `"75"`. The constructor for this class is marked as internal. Third-party code should not call the constructor directly or create subclasses that extend the `BrowserFetcher` class. ## Example An example of using BrowserFetcher to download a specific version of Chromium and running Puppeteer against it: ```ts const browserFetcher = puppeteer.createBrowserFetcher(); const revisionInfo = await browserFetcher.download('533271'); const browser = await puppeteer.launch({ executablePath: revisionInfo.executablePath, }); ``` **NOTE** BrowserFetcher is not designed to work concurrently with other instances of BrowserFetcher that share the same downloads directory. ## Methods | Method | Modifiers | Description | | ------------------------------------------------------------------------------ | --------- | --------------------------------------------------------------- | | [canDownload(revision)](./puppeteer.browserfetcher.candownload.md) | | Initiates a HEAD request to check if the revision is available. | | [download(revision, progressCallback)](./puppeteer.browserfetcher.download.md) | | Initiates a GET request to download the revision from the host. | | [host()](./puppeteer.browserfetcher.host.md) | | | | [localRevisions()](./puppeteer.browserfetcher.localrevisions.md) | | | | [platform()](./puppeteer.browserfetcher.platform.md) | | | | [product()](./puppeteer.browserfetcher.product.md) | | | | [remove(revision)](./puppeteer.browserfetcher.remove.md) | | | | [revisionInfo(revision)](./puppeteer.browserfetcher.revisioninfo.md) | | |