Storage: length property

The length read-only property of the Storage interface returns the number of data items stored in a given Storage object.


The number of items stored in the Storage object.


The following function adds three data items to the local storage for the current domain, then returns the number of items in the storage:

function populateStorage() {
  localStorage.setItem("bgcolor", "yellow");
  localStorage.setItem("font", "Helvetica");
  localStorage.setItem("image", "cats.png");

  return localStorage.length; // Should return 3

Note: For a real-world example, see our Web Storage Demo.


HTML Standard
# dom-storage-length-dev

Browser compatibility

BCD tables only load in the browser

See also