files/en-us/web/api/htmlbuttonelement/checkvalidity/index.md
{{APIRef("HTML DOM")}}
The checkValidity() method of the {{domxref("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 {{domxref("HTMLElement/invalid_event", "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 {{HTMLElement("button")}} element's {{domxref("HTMLButtonElement/type", "type")}} is "button" or "reset", because such buttons are never candidates for constraint validation.
[!NOTE] An HTML {{htmlelement("button")}} element of the
"submit"type with a non-null {{domxref("HTMLButtonElement.validationMessage", "validationMessage")}} is considered invalid, will match the CSS {{cssxref(":invalid")}} pseudo-class, and will causecheckValidity()to return false. Use the {{domxref("HTMLButtonElement.setCustomValidity()")}} method to set the {{domxref("HTMLButtonElement.validationMessage")}} to the empty string to set the {{domxref("HTMLButtonElement.validity", "validity")}} state to be valid.
checkValidity()
None.
Returns true if the element's value has no validity problems; otherwise, returns false.
In the following example, calling checkValidity() returns either true or false.
const element = document.getElementById("myButton");
console.log(element.checkValidity());
{{Specifications}}
{{Compat}}