Node: previousSibling property
{{APIRef("DOM")}} 
The read-only previousSibling property of the {{domxref("Node")}}  interface
returns the node immediately preceding the specified one in its parent’s
{{domxref("Node.childNodes", "childNodes")}}  list,
or null if the specified node is the first in that list.
[!NOTE] Browsers insert text nodes into a document to represent whitespace in the source markup. Therefore a node obtained, for example, using
Node.firstChildorNode.previousSiblingmay refer to a whitespace text node rather than the actual element the author intended to get.See Working with whitespace in the DOM for more information.
You can use
previousElementSiblingto get the previous element node (skipping text nodes and any other non-element nodes).To navigate the opposite way through the child nodes list use Node.nextSibling.
Value
A {{domxref("Node")}}  representing the previous sibling of the current node,
or null if there are none.
Examples
The following examples demonstrate how previousSibling works with and without text nodes mixed in with elements.
First example
In this example, we have a series of img elements directly adjacent to each other, with no whitespace between them.
<img id="b0" /><img id="b1" /><img id="b2" />
document.getElementById("b1").previousSibling; // <img id="b0">
document.getElementById("b2").previousSibling.id; // "b1"
Second example
In this example, there are whitespace text nodes (line breaks) between the {{htmlelement("span")}}  elements.
<span id="b0"></span>
<span id="b1"></span>
<span id="b2"></span>
document.getElementById("b1").previousSibling; // #text
document.getElementById("b1").previousSibling.previousSibling; // <span id="b0">
document.getElementById("b2").previousSibling.previousSibling; // <span id="b1">
document.getElementById("b2").previousSibling; // #text
document.getElementById("b2").previousSibling.id; // undefined
Specifications
{{Specifications}} 
Browser compatibility
{{Compat}} 
See also
- {{domxref("Node.nextSibling")}}
- {{domxref("Element.previousElementSibling")}}