Zend_Validate_Date allows you to validate if a given value contains a date. This validator validates also localized input. The following options are supported for Zend_Validate_Date: format: Sets the format which is used to write the date. locale: Sets the locale which will be used to validate date values. The easiest way to validate a date is by using the default date format. It is used when no locale and no format has been given. isValid('2000-10-10'); // returns true $validator->isValid('10.10.2000'); // returns false ]]> The default date format for Zend_Validate_Date is 'yyyy-MM-dd'. Zend_Validate_Date validates also dates which are given in a localized format. By using the locale option you can define the locale which the date format should use for validation. 'de')); $validator->isValid('10.Feb.2010'); // returns true $validator->isValid('10.May.2010'); // returns false ]]> The locale option sets the default date format. In the above example this is 'dd.MM.yyyy' which is defined as default date format for 'de'. Zend_Validate_Date supports also self defined date formats. When you want to validate such a date you can use the format option. 'yyyy')); $validator->isValid('2010'); // returns true $validator->isValid('May'); // returns false ]]> Of course you can combine format and locale. In this case you can also use localized month or daynames. 'yyyy MMMM', 'locale' => 'de')); $validator->isValid('2010 Dezember'); // returns true $validator->isValid('2010 June'); // returns false ]]>