The Mobile Compatibility Calculator is a free Chrome add-on developed by joon1251. This tool allows users to calculate the mobile compatibility of a webpage. After the webpage has fully loaded, users can use the calculator to determine the compatibility score. The score is based on the following criteria:

• 85 or above: Good
• 65 or above: Average
• Below 64: Poor

With its simple and straightforward interface, the Mobile Compatibility Calculator is easy to use. It provides a quick and convenient way to assess the mobile friendliness of a webpage. Whether you are a developer or a user, this add-on can be a valuable tool in ensuring that your website is optimized for mobile devices. Please note that the calculator should only be used after the webpage has completely loaded to ensure accurate results.