ValidityState

{{APIRef("HTML DOM")}} 

The ValidityState interface represents the validity states that an element can be in, with respect to constraint validation. Together, they help explain why an element’s value fails to validate, if it’s not valid.

Instance properties

For each of these Boolean properties, a value of true indicates that the specified reason validation may have failed is true, with the exception of the valid property, which is true if the element’s value obeys all constraints.

• {{domxref("ValidityState.badInput", "badInput")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the user has provided input that the browser is unable to convert.
• {{domxref("ValidityState.customError", "customError")}}  {{ReadOnlyInline}} 
  • : A boolean value indicating whether the element’s custom validity message has been set to a non-empty string by calling the element’s {{domxref('HTMLInputElement.setCustomValidity', 'setCustomValidity()')}}  method.
• {{domxref("ValidityState.patternMismatch", "patternMismatch")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the value does not match the specified pattern, and false if it does match. If true, the element matches the {{cssxref(":invalid")}}  CSS pseudo-class.
• {{domxref("ValidityState.rangeOverflow", "rangeOverflow")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the value is greater than the maximum specified by the max attribute, or false if it is less than or equal to the maximum. If true, the element matches the {{cssxref(":invalid")}}  and {{cssxref(":out-of-range")}}  and CSS pseudo-classes.
• {{domxref("ValidityState.rangeUnderflow", "rangeUnderflow")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the value is less than the minimum specified by the min attribute, or false if it is greater than or equal to the minimum. If true, the element matches the {{cssxref(":invalid")}}  and {{cssxref(":out-of-range")}}  CSS pseudo-classes.
• {{domxref("ValidityState.stepMismatch", "stepMismatch")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the value does not fit the rules determined by the step attribute (that is, it’s not evenly divisible by the step value), or false if it does fit the step rule. If true, the element matches the {{cssxref(":invalid")}}  CSS pseudo-class.
• {{domxref("ValidityState.tooLong", "tooLong")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the value exceeds the specified maxlength for {{domxref("HTMLInputElement")}}  or {{domxref("HTMLTextAreaElement")}}  objects, or false if its length is less than or equal to the maximum length. Note: This property is never true in Gecko, because elements’ values are prevented from being longer than maxlength. If true, the element matches the {{cssxref(":invalid")}}  and {{cssxref(":out-of-range")}}  CSS pseudo-classes.
• {{domxref("ValidityState.tooShort", "tooShort")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the value fails to meet the specified minlength for {{domxref("HTMLInputElement")}}  or {{domxref("HTMLTextAreaElement")}}  objects, or false if its length is greater than or equal to the minimum length. If true, the element matches the {{cssxref(":invalid")}}  and {{cssxref(":out-of-range")}}  CSS pseudo-classes.
• {{domxref("ValidityState.typeMismatch", "typeMismatch")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the value is not in the required syntax (when type is email or url), or false if the syntax is correct. If true, the element matches the {{cssxref(":invalid")}}  CSS pseudo-class.
• {{domxref("ValidityState.valid", "valid")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the element meets all its validation constraints, and is therefore considered to be valid, or false if it fails any constraint. If true, the element matches the {{cssxref(":valid")}}  CSS pseudo-class; the {{cssxref(":invalid")}}  CSS pseudo-class otherwise.
• {{domxref("ValidityState.valueMissing", "valueMissing")}}  {{ReadOnlyInline}} 
  • : A boolean value that is true if the element has a required attribute, but no value, or false otherwise. If true, the element matches the {{cssxref(":invalid")}}  CSS pseudo-class.

Specifications

{{Specifications}} 

Browser compatibility

{{Compat}} 

See also

• Guide: Constraint validation
• Tutorial: Form data validation