MBC Calculator is a Chrome extension developed by oelbaytam. It falls under the category of Browsers and specifically the subcategory of Add-ons & Tools. As a free tool, it aims to assist marble card enthusiasts by calculating the XP required to level up a marble card from a specific initial level to a desired level.

With MBC Calculator, users can easily determine the amount of XP needed to achieve their desired marble card level. This extension provides a convenient shortcut to the marble.cards website, allowing users to quickly navigate to the site for further information and resources.

It's important to note that MBC Calculator is not an official extension developed by marble cards. Instead, it is a creation of an admirer who wants to enhance the marbling experience for everyone. This extension serves as a useful tool for those who are passionate about marble cards and want to streamline their leveling process.