The defaultValue property of the HTMLInputElement interface indicates the original (or default) value of the <input> element. It reflects the element's value attribute.
A string representing the default, or original, value of the <input> element.
Given the following HTML:
<label for="planet">Which planet were you born on?</label>
<input id="planet" type="text" value="Azarath" />The following will provide the same results, no matter what the user enters into the text input.
const inputElement = document.querySelector("#planet");
console.log(`Original value: ${inputElement.defaultValue}`); // "Original value: Azarath"