Device Viewport Tester

Test website viewports on different mobile devices with this utility, allowing users to verify how websites adapt to different screen sizes and orientations.

Device Viewport Tester is available to install from Firefox Browser Add-ons and for download from this page. It has 2 active users The latest version is 1.0, and it was published a year ago.

Install from Firefox Browser Add-ons
View source code
Total download count: 0 (Only count downloads from Firefox-Stats)

All available versions

You can find the current and older versions of Device Viewport Tester here. You can download the archived versions or inspect their source codes.

As a free user, you can only download the latest version.

Upgrade to download older versions
 1 version available for download.

Install XPI file

  1. Simply drag-and-drop the XPI into Firefox to install the add-on.

Install ZIP file

  2. In Firefox browser, go to about:addons to open Add-ons Manager
  3. Click on , then select Install Add-on From File
  4. Select the Device Viewport Tester ZIP file from step 1. Device Viewport Tester is now installed on your browser.