
The CSS border-image-width property defines the width of the border-image.
Demo:
Click the “Try it” button to change the value of the border-image-width property 10px to 20px 30px:
Hello World!
Syntax:
border-image-width: length|number|%|auto;
length – a length unit (in px) defining the size of the border-width.
number – represents multiples of the corresponding border-width (the default value is 1).
% – refers to the size of the border image area: the width of the area for horizontal offsets, the height for vertical offsets.
auto – if defined, the width is the intrinsic width or height of the corresponding image slice.
Example:
<!DOCTYPE html>
<html>
<head>
<style>
#borderimg-1 {
border: 10px solid transparent;
padding: 15px;
border-image-source: url(https://lenadesign.org/wp-content/uploads/2021/09/border-1.png);
border-image-repeat: round;
border-image-slice: 30;
border-image-width: 10px;
}
#borderimg-2 {
border: 10px solid transparent;
padding: 15px;
border-image-source: url(https://lenadesign.org/wp-content/uploads/2021/09/border-1.png);
border-image-repeat: round;
border-image-slice: 30;
border-image-width: 15px;
}
#borderimg-3 {
border: 10px solid transparent;
padding: 15px;
border-image-source: url(https://lenadesign.org/wp-content/uploads/2021/09/border-1.png);
border-image-repeat: round;
border-image-slice: 30;
border-image-width: 20px;
}
</style>
</head>
<body>
<p id="borderimg-1">border-image-width: 10px;</p>
<p id="borderimg-2">border-image-width: 15px;</p>
<p id="borderimg-3">border-image-width: 20px;</p>
</body>
</html>
Output:
border-image-width: 10px;
border-image-width: 15px;
border-image-width: 20px;
The original image:

Enjoy coding!
Read also:
Advanced CSS Border-radius/ Drop Shape, Lemon Shape, Leaf Shape & Egg Shape