files/en-us/web/api/svgfediffuselightingelement/width/index.md
{{APIRef("SVG")}}
The width read-only property of the {{domxref("SVGFEDiffuseLightingElement")}} interface describes the horizontal size of an SVG filter primitive as a {{domxref("SVGAnimatedLength")}}.
It reflects the {{SVGElement("feDiffuseLighting")}} element's {{SVGAttr("width")}} filter primitive attribute. The filter lights an image using the alpha channel as a bump map. The attribute is a <length> or a <percentage> relative to the width of the filter region. The default value is 100%. The property value is a length in user coordinate system units.
An {{domxref("SVGAnimatedLength")}}.
const feDiffuseLighting = document.querySelector("feDiffuseLighting");
const horizontalSize = feDiffuseLighting.width;
console.log(horizontalSize.baseVal.value); // the `width` value
{{Specifications}}
{{Compat}}