HTMLButtonElement: checkValidity() method

The checkValidity() method of the HTMLButtonElement interface returns a boolean value which indicates if the element meets any constraint validation rules applied to it. If false, the method also fires an invalid event on the element. Because there’s no default browser behavior for checkValidity(), canceling this invalid event has no effect. It always returns true if the <button> element’s type is "button" or "reset", because such buttons are never candidates for constraint validation.

[!NOTE] An HTML <button> element of the "submit" type with a non-null validationMessage is considered invalid, will match the CSS :invalid pseudo-class, and will cause checkValidity() to return false. Use the setCustomValidity() method to set the validationMessage to the empty string to set the validity state to be valid.

Syntax

checkValidity()

Parameters

None.

Return value

Returns true if the element’s value has no validity problems; otherwise, returns false.

Examples

In the following example, calling checkValidity() returns either true or false.

const element = document.getElementById("myButton");
console.log(element.checkValidity());

Specifications

Browser compatibility

See also

• reportValidity()
• <button>
• <form>
• Learn: Client-side form validation
• Guide: Constraint validation
• CSS :valid and :invalid pseudo-classes