Cross Multiply Calculator is a free Chrome extension developed by Hélder Pestana. It falls under the category of Browsers and specifically the subcategory of Add-ons & Tools. The program allows users to calculate proportional values using the cross multiplication rule or vector cross product calculation, commonly known as the Rule of Three calculation.

With Cross Multiply Calculator, users can easily resize images, videos, and other elements while maintaining proportional values. The extension simplifies the process of calculating cross multiply proportions, ratios, and sizes. Whether you need to resize an image for a website or adjust the dimensions of a video, this tool provides a quick and efficient solution.

The extension is straightforward to use and provides accurate calculations. It is a handy tool for anyone who frequently works with proportional values and needs to resize elements while maintaining their proportions. Cross Multiply Calculator is a valuable addition to any Chrome user's toolkit.