``input``
~~~~~~~~~

**type**: ``string`` **default**: ``datetime``

The format of the *input* data - i.e. the format that the date is stored
on your underlying object. Valid values are:

* ``string`` (e.g. ``2011-06-05``)
* ``datetime`` (a ``DateTime`` object)
* ``datetime_immutable`` (a ``DateTimeImmutable`` object)
* ``array`` (e.g. ``['year' => 2011, 'month' => 06, 'day' => 05]``)
* ``timestamp`` (e.g. ``1307232000``)

The value that comes back from the form will also be normalized back into
this format.

.. include:: /reference/forms/types/options/_date_limitation.rst.inc
