viewBox

The viewBox attribute defines the position and dimension, in user space, of an SVG viewport.

The value of the viewBox attribute is a list of four numbers separated by whitespace and/or a comma: min-x, min-y, width, and height. min-x and min-y represent the smallest X and Y coordinates that the viewBox may have (the origin coordinates of the viewBox) and the width and height specify the viewBox size. The resulting viewBox is a rectangle in user space mapped to the bounds of the viewport of an SVG element (not the browser viewport). When an SVG contains a viewBox attribute (often in combination with a preserveAspectRatio attribute), a transform stretches or resizes the SVG viewport to fit a particular container element.

Elements

You can use this attribute with the SVG elements described in the sections below.

`<marker>`

For <marker>, viewBox defines the position and dimension for the content of the <marker> element.

Value	<number>,? <number>,? <number>,? <number>
Default value	none
Animatable	Yes

`<pattern>`

For <pattern>, viewBox defines the position and dimension for the content of the pattern tile.

Value	<number>,? <number>,? <number>,? <number>
Default value	none
Animatable	Yes

`<svg>`

For <svg>, viewBox defines the position and dimension for the content of the <svg> element.

Value	<number>,? <number>,? <number>,? <number>
Default value	none
Animatable	Yes

`<symbol>`

For <symbol>, viewBox defines the position and dimension for the content of the <symbol> element.

Value	<number>,? <number>,? <number>,? <number>
Default value	none
Animatable	Yes

`<view>`

For <view>, viewBox defines the position and dimension for the content of the <view> element.

Value	<number>,? <number>,? <number>,? <number>
Default value	none
Animatable	Yes

Examples

html,
body,
svg {
  height: 100%;
  vertical-align: top;
}
svg:not(:root) {
  display: inline-block;
}

The code snippet below includes three <svg>s with different viewBox attribute values and identical <rect> and <circle> descendants creating very different results. The size of <rect> is defined using relative units, so the visual size of the square produced looks unchanged regardless of the viewBox value. The radius length r attribute of the <circle> is the same in each case, but this user unit value is resolved against the size defined in the viewBox, producing different results in each case.

html

<svg viewBox="0 0 100 100" xmlns="http://www.w3.org/2000/svg">
  <rect x="0" y="0" width="100%" height="100%" />
  <circle cx="50%" cy="50%" r="4" fill="white" />
</svg>

<svg viewBox="0 0 10 10" xmlns="http://www.w3.org/2000/svg">
  <rect x="0" y="0" width="100%" height="100%" />
  <circle cx="50%" cy="50%" r="4" fill="white" />
</svg>

<svg viewBox="-5 -5 10 10" xmlns="http://www.w3.org/2000/svg">
  <rect x="0" y="0" width="100%" height="100%" />
  <circle cx="50%" cy="50%" r="4" fill="white" />
</svg>

The user units of r="4" are resolved against the viewBox sizes, creating dramatically different circle sizes. The exact effect of the viewBox attribute is influenced by the preserveAspectRatio attribute.

Note: Values for width or height lower or equal to 0 disable rendering of the element.

Specifications

Specification
Scalable Vector Graphics (SVG) 2 # ViewBoxAttribute