The SVGGraphicsElement.getBBox() method allows us to determine the coordinates of the smallest rectangle in which the object fits. The coordinates returned are with respect to the current SVG space (after the application of all geometry attributes on all the elements contained in the target element).
Note: getBBox() must return the actual bounding box at the time the method was called—even in case the element has not yet been rendered. It also does not account for any transformation applied to the element or its parents.
Note: getBBox returns different values than getBoundingClientRect(), as the latter returns value relative to the viewport
getBBox()
getBBox(options)
The returned value is a SVGRect object, which defines the bounding box. This value is irrespective of any transformation attribute applied to it or the parent elements.
<svg viewBox="0 0 200 200" xmlns="http://www.w3.org/2000/svg">
<g id="group_text_1">
<text x="5" y="16" transform="scale(2, 2)">Hello World!</text>
<text x="8" y="32" transform="translate(0 20) scale(1.25 1)">
Hello World Again!
</text>
</g>
<rect id="rect_1" stroke="#00ff00" stroke-width="3" fill="none"></rect>
<rect id="rect_2" stroke="#ff0000" stroke-width="3" fill="none"></rect>
</svg>
const rectBBox = document.querySelector("#rect_1");
const rectBoundingClientRect = document.querySelector("#rect_2");
const groupElement = document.querySelector("#group_text_1");
const bboxGroup = groupElement.getBBox();
rectBBox.setAttribute("x", bboxGroup.x);
rectBBox.setAttribute("y", bboxGroup.y);
rectBBox.setAttribute("width", bboxGroup.width);
rectBBox.setAttribute("height", bboxGroup.height);
const boundingClientRectGroup = groupElement.getBoundingClientRect();
rectBoundingClientRect.setAttribute("x", boundingClientRectGroup.x);
rectBoundingClientRect.setAttribute("y", boundingClientRectGroup.y);
rectBoundingClientRect.setAttribute("width", boundingClientRectGroup.width);
rectBoundingClientRect.setAttribute("height", boundingClientRectGroup.height);