HTMLSelectElement: selectedIndex property

The HTMLSelectElement.selectedIndex property is a long that reflects the index of the first or last selected <option> element, depending on the value of multiple. The value -1 indicates that no element is selected.

Value

A number.

Examples

HTML

html

<p id="p">selectedIndex: 0</p>

<select id="select">
  <option selected>Option A</option>
  <option>Option B</option>
  <option>Option C</option>
  <option>Option D</option>
  <option>Option E</option>
</select>

JavaScript

const selectElem = document.getElementById("select");
const pElem = document.getElementById("p");

// When a new <option> is selected
selectElem.addEventListener("change", () => {
  const index = selectElem.selectedIndex;
  // Add that data to the <p>
  pElem.textContent = `selectedIndex: ${index}`;
});

Specifications

Specification
HTML Standard # dom-select-selectedindex-dev

Browser compatibility

BCD tables only load in the browser