Font Size in CSS

When working with CSS, font size is an important aspect that affects the visual representation and user experience of a web page. In this guide, we will explore the different ways to specify font size in CSS using the font-size property.

Syntax

The syntax for setting font size in CSS is as follows:

selector {
  font-size: value;
}

The selector refers to the HTML element you want to style, while value is the actual size of the font you want to use.

Types of Values for Font Size

There are different units of measurement that can be used to define the value of font-size:

1. Absolute units: These are fixed sizes that do not change relative to other units. Examples of absolute units include px, pt, and in.

2. Relative units: These are sizes that are relative to other elements. Examples of relative units include em, ex, rem, vh, vw, %.

Absolute Units

Absolute units are commonly used for font sizes in CSS. The most commonly used absolute unit is px.

selector {
  font-size: 16px;
}

The above example sets the font size of the specified element to 16 pixels.

Relative Units

Relative units are useful in situations where you want the font size to be proportional to other elements on the page. For example, em units are relative to the font size of the parent element, while rem units are relative to the font size of the root element.

Example:

.parent {
  font-size: 16px;
}

.child {
  font-size: 1em; /* results in font size of 16px as it's relative to the parent */
}

.root {
  font-size: 20px;
}

.child-2 {
  font-size: 1.5rem; /* results in font size of 30px as it's relative to the root element */
}

In the above example, child element has a font size of 1em, which is relative to the font size of the parent element (16px). child-2 element has a font size of 1.5rem, which is relative to the font-size of the root element (20px).

Using Percentages

Percentages can also be used as a value for font-size. In this case, the font size is calculated relative to the font size of the parent element.

Example:

.parent {
  font-size: 16px;
}

.child {
  font-size: 150%;
}

In the above example, child element has a font size of 150% of the font size of the parent element. This results in a font size of 24px (150% of 16px).

Conclusion

Font size is an essential aspect of web design, and CSS provides different ways of specifying font size using absolute units, relative units and percentages. By understanding these concepts, you can easily set the right font size for your web page to improve user experience.