HTMLInputElement: selectionStart property

The selectionStart property of the HTMLInputElement interface is a number that represents the beginning index of the selected text. When nothing is selected, then returns the position of the text input cursor (caret) inside of the <input> element.

Note: According to the WHATWG forms spec selectionStart property applies only to inputs of types text, search, URL, tel, and password. In modern browsers, throws an exception while setting selectionStart property on the rest of input types. Additionally, this property returns null while accessing selectionStart property on non-text input elements.

If selectionStart is greater than selectionEnd, then both are treated as the value of selectionEnd.

Value

A non-negative number.

Examples

HTML

html
<!-- use selectionStart on non text input element -->
<label for="color">selectionStart property on type=color</label>
<input id="color" type="color" />

<!-- use selectionStart on text input element -->
<fieldset>
  <legend>selectionStart property on type=text</legend>
  <label for="statement">Select 'mdn' word from the text : </label>
  <input
    type="text"
    id="statement"
    value="The mdn is a documentation repository." />
  <button id="statement-btn">Select mdn text</button>
</fieldset>

JavaScript

js
const inputElement = document.getElementById("statement");
const statementBtn = document.getElementById("statement-btn");
const colorStart = document.getElementById("color");

statementBtn.addEventListener("click", () => {
  inputElement.selectionStart = 4;
  inputElement.selectionEnd = 7;
  inputElement.focus();
});

// open browser console to verify output
console.log(colorStart.selectionStart); // Output : null

Result

Specifications

Specification
HTML Standard
# dom-textarea/input-selectionstart

Browser compatibility

BCD tables only load in the browser

See also