files/en-us/web/api/svgfecompositeelement/y/index.md
{{APIRef("SVG")}}
The y read-only property of the {{domxref("SVGFECompositeElement")}} interface describes the vertical coordinate of the position of an SVG filter primitive as a {{domxref("SVGAnimatedLength")}}.
It reflects the {{SVGElement("feComposite")}} element's {{SVGAttr("y")}} filter primitive attribute value. The <feComposite> SVG filter primitive combines two input images using a Porter-Duff compositing operation. The attribute is a <length> or <percentage>. The <coordinate> is a length in the user coordinate system that is the given distance from the origin of the filter along the y-axis. If the y attribute is a percent value, the property value is a relative to the height of the filter region in user coordinate system units. The default value is 0.
An {{domxref("SVGAnimatedLength")}}.
const feComposite = document.querySelector("feComposite");
const topPosition = feComposite.y;
console.log(topPosition.baseVal.value); // the `y` value
{{Specifications}}
{{Compat}}