Get width/height of SVG element

Question

What is the proper way to get the dimensions of an svg element?

http://jsfiddle.net/langdonx/Xkv3X/

Chrome 28:

style x
client 300x100
offset 300x100

IE 10:

stylex 
client300x100 
offsetundefinedxundefined 

FireFox 23:

"style" "x"
"client" "0x0"
"offset" "undefinedxundefined"

There are width and height properties on svg1, but .width.baseVal.value is only set if I set the width and height attributes on the element.

---

The fiddle looks like this:

HTML

<svg id="svg1" xmlns="http://www.w3.org/2000/svg" version="1.1">
    <circle cx="50" cy="50" r="40" stroke="black" stroke-width="1" fill="red" />
    <circle cx="150" cy="50" r="40" stroke="black" stroke-width="1" fill="green" />
    <circle cx="250" cy="50" r="40" stroke="black" stroke-width="1" fill="blue" />
</svg>

JS

var svg1 = document.getElementById('svg1');

console.log(svg1);
console.log('style', svg1.style.width + 'x' + svg1.style.height);
console.log('client', svg1.clientWidth + 'x' + svg1.clientHeight);
console.log('offset', svg1.offsetWidth + 'x' + svg1.offsetHeight);

CSS

#svg1 {
    width: 300px;
    height: 100px;
}

Answer 1

Use the getBBox function:

The SVGGraphicsElement.getBBox() method allows us to determine the coordinates of the smallest rectangle in which the object fits. [...]

http://jsfiddle.net/Xkv3X/1/

var bBox = svg1.getBBox();
console.log('XxY', bBox.x + 'x' + bBox.y);
console.log('size', bBox.width + 'x' + bBox.height);