ValidityState: rangeUnderflow property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since December 2018.

The read-only rangeUnderflow property of a ValidityState object indicates if the value of an <input>, after having been edited by the user, does not conform to the constraints set by the element's min attribute.

If the field is numeric in nature, including the date, month, week, time, datetime-local, number and range types and a min value is set, if the value doesn't conform to the constraints set by the min value, the rangeUnderflow property will be true.

Given the following:

<input type="number" min="20" max="40" step="2" />

if value < 20, rangeUnderflow will be true. When true, the element matches the :invalid and :out-of-range CSS pseudo-classes.


HTML Standard
# dom-validitystate-rangeunderflow

Browser compatibility

BCD tables only load in the browser

See also