HTML | DOM Style fontSize Property

Last Updated : 08 Aug, 2022

The fontSize property is used to set or get the font size of characters in a word should appear.

Syntax:

It returns the fontSize property.

object.style.fontSize

It sets the fontSize Property.

object.style.fontSize = "value|initial|inherit"

Property Values:

Value	Description
xx-small x-small small medium large x-large xx-large	Predefine sizes of font
smaller	Decreases by one relative unit of the font-size
larger	Increases by one relative unit of the font-size
length	Font-size in length unit
%	% of the parent element's font size
initial	Set default value
inherit	Inherit property from its parent value

Return value: It returns the font size of the text of element.

Example-1: Change font size into small.

html

<!DOCTYPE html>
<html>

<head>
    <title>DOM Style fontSize Property </title>
</head>

<body>
    <center>
        <p style="color: green;
                  width: 100%;
                  font-size: 30px; 
                  font-weight: bold;" 
           id="Geek1">
            GeeksForGeeks
        </p>

        <h2>DOM Style fontSize Property </h2>
        <br>
        <button type="button" onclick="myGeeks()">
            Click to change
        </button>

        <script>
            function myGeeks() {
                
              
                //  Change font size in to small.
                document.getElementById(
               "Geek1").style.fontSize = "small";
            }
        </script>
    </center>
</body>

</html>

Output:

Before click on button:

After click on button:

Example-2: Change font-size into xx-large.

html

<!DOCTYPE html>
<html>

<head>
    <title>DOM Style fontSize Property </title>
</head>

<body>
    <center>
        <p style="color: green; 
                  width: 100%; 
                  font-size: 10px; 
                  font-weight: bold;" 
           id="Geek1">
            GeeksForGeeks
        </p>

        <h2>DOM Style fontSize Property </h2>
        <br>
        <button type="button" onclick="myGeeks()">
            Click to change
        </button>

        <script>
            function myGeeks() {
              
                //  change into xx-large.
                document.getElementById(
                  "Geek1").style.fontSize = "xx-large";
            }
        </script>
    </center>
</body>

</html>

Output:

Before click on button:

After click on button:

Example-3: Change font-size using length unit.

html

<!DOCTYPE html>
<html>

<head>
    <title>DOM Style fontSize Property </title>
</head>

<body>
    <center>
        <p style="color: green;
                  width: 100%;
                  font-size: 10px; 
                  font-weight: bold;"
           id="Geek1">
            GeeksForGeeks
        </p>

        <h2>DOM Style fontSize Property </h2>
        <br>
        <button type="button" onclick="myGeeks()">
            Click to change
        </button>

        <script>
            function myGeeks() {
              
                //  Change font size from 
                //  from 10px to 30px
                document.getElementById(
                  "Geek1").style.fontSize = "30px";
            }
        </script>
    </center>
</body>

</html>

Output:

Before click on button:

After click on button:

Example-4: Change font-size using '%'

html

<!DOCTYPE html>
<html>

<head>
    <title>DOM Style fontSize Property </title>
</head>

<body>
    <center>
        <p style="color: green;
                  width: 100%; 
                  font-size: 10px; 
                  font-weight: bold;"
           id="Geek1">
            GeeksForGeeks
        </p>

        <h2>DOM Style fontSize Property </h2>
        <br>
        <button type="button" onclick="myGeeks()">
            Click to change
        </button>

        <script>
            function myGeeks() {
              
                //  Change font-size from 100% to 200%
                document.getElementById(
                  "Geek1").style.fontSize = "200%";
            }
        </script>
    </center>
</body>

</html>