Get width in pixels from element with style set with %?

Question

I have this element:

<div style="width: 100%; height: 10px;"></div> 

I want to get it's width in pixels. I just tried this:

document.getElementById('banner-contenedor').style.width 

Which returns 100%. Is it possible to actually get the element's width in pixels with JavaScript?

Answer 1

document.getElementById('banner-contenedor').clientWidth 

Answer 2

You want to get the computed width. Try: .offsetWidth

(I.e: this.offsetWidth='50px' or var w=this.offsetWidth)

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