The viewBox read-only property of the SVGMarkerElement interface returns an SVGAnimatedRect object which contains the values set by the viewBox attribute on the <marker>.


let viewBox = SVGMarkerElement.viewBox;


An SVGAnimatedRect object. The baseVal property of this object returns an SVGRect object, from which can be returned the x and y co-ordinates, plus the width and height of the <marker> viewBox attribute.


This example demonstrates how to return the value of the width set for the viewBox attribute of <marker>.

<svg id="svg" viewBox="0 0 100 100" xmlns="">
    <marker id="arrow" viewBox="0 0 10 10" refX="5" refY="5"
        viewBox="xMidYMid meet"
        markerWidth="6" markerHeight="6"
      <path d="M 0 0 L 10 5 L 0 10 z" />
let marker = document.getElementById("arrow");
console.log(marker.viewBox.baseVal.width); //10


Specification Status Comment
Scalable Vector Graphics (SVG) 2
The definition of 'SVGMarkerElement.viewBox' in that specification.
Candidate Recommendation Initial definition

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