Example
Accepts a mathematical expression and returns a numerical value.
It is especially useful when working with different types of units (e.g. subtracting a px value from a percentage) to calculate the value of an attribute.
+, -, /, and * operators can all be used, and parentheses can be added to specify the order of operations if necessary.
Use calc() to calculate the width of a div element:
#div1 {
position: absolute;
left: 50px;
width: calc(100% - 100px);
border: 1px solid black;
background-color: yellow;
padding: 5px;
text-align: center;
}
Use calc() to determine the position of a background-image:
background-position: calc(50% + 17px) calc(50% + 10px), 50% 50%;
Use calc() to determine the height of an element:
height: calc(100% - 20px);
