The available documentation does not verify that the URLbox Chrome extension supports custom viewport sizes—or establish which extension the title refers to. It would be misleading to give extension-specific URL steps without an extension listing or help page. If you mean the Urlbox screenshot API, its documented method is to set the width and height parameters in pixels.
What is—and isn’t—documented about the extension
Urlbox’s official materials describe a service that renders URLs and HTML as screenshots, PDFs, videos, and extracted content. They document API options, but the available pages do not identify a URLbox Chrome extension or explain how to change viewport dimensions in an extension.
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That distinction matters: the API syntax below is verified for an API render link, not for a Chrome extension. Don’t assume that adding these parameters to an extension URL will work. To get extension-specific instructions, first confirm the extension’s exact name and publisher in its Chrome Web Store listing, then consult that publisher’s help page.
If you mean the Urlbox screenshot API
The Urlbox API uses width and height to set the browser viewport in pixels. Width controls the horizontal dimension; height controls the vertical dimension. The documented default viewport is 1280 × 1024 pixels. The Urlbox options documentation lists these controls and defaults: Urlbox render options.
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Set dimensions in a render link
The official quick start demonstrates a 390 × 844 pixel viewport in this API link:
https://api.urlbox.com/v1/api-key/png?url=github.com&width=390&height=844&thumb_width=200
Here, width=390 and height=844 set the viewport dimensions; thumb_width=200 is also present in the quick-start example. The 390 × 844 dimensions are an example configuration, not a required device size or an extension setting. See the Urlbox quick start.
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Choose dimensions for the result you need
The documentation defines the two pixel dimensions but does not prescribe a single best size. Choose a width and height that match the layout you need to render. The API example should be treated as an API configuration only; it does not establish how to set dimensions in a browser extension.
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curl -G "https://api.screenshotneo.com/v1/shot" -d access_key=YOUR_API_KEY --data-urlencode url=https://stripe.com -o shot.webp
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