If an element is set to width: 100vw; and there is a vertical scrollbar the width of the element will be equal to the viewport plus the width of the scrollbar.<
width: 100vw;
Here's my solution to the problem of 100vw adding a horizontal scroll:
html { width: calc(100% + calc(100vw - 100%)); overflow-x: hidden; } .box { width: calc(100% + calc(100vw - 100%)); }