Css calculate height dynamically based on CSS Width & Height Calculator. It's free to sign up and bid on jobs. It is rather easy: CSS calculates height based on width and other elements. Simply put, it is a new function in CSS3, short for calculate. So I will show you most of those methods to get the height and width of an HTML element . Step 2) Add CSS: Add a percentage value for padding-top to maintain the aspect ratio of the DIV. Enter the unit type you would like to convert from and the width or height you would like to convert from, then press calculate & this calculator will convert your 1. on CSS, It is not even possible, on javascript you would not have any problem, I would recommend the use of other varial values such as width: 100vw relative of width of the Use calc () to calculate the width of a