Using DateDataParser

dateparser.parse() uses a default parser which tries to detect language every time it is called and is not the most efficient way while parsing dates from the same source.

DateDataParser provides an alternate and efficient way to control language detection behavior.

The instance of DateDataParser reduces the number of applicable languages, until only one or no language is left. It assumes the previously detected language for all the subsequent dates supplied.

This class wraps around the core dateparser functionality, and by default assumes that all of the dates fed to it are in the same language.

class*args, **kwargs)[source]

Class which handles language detection, translation and subsequent generic parsing of string representing date and/or time.

  • languages (list) – A list of two letters language codes, e.g. [‘en’, ‘es’]. If languages are given, it will not attempt to detect the language.
  • allow_redetect_language (bool) – Enables/disables language re-detection.
  • settings (dict) – Configure customized behavior using settings defined in dateparser.conf.Settings.

A parser instance


ValueError - Unknown Language, TypeError - Languages argument must be a list

get_date_data(date_string, date_formats=None)[source]

Parse string representing date and/or time in recognizable localized formats. Supports parsing multiple languages and timezones.

  • date_string (str|unicode) – A string representing date and/or time in a recognizably valid format.
  • date_formats (list) – A list of format strings using directives as given here. The parser applies formats one by one, taking into account the detected languages.

a dict mapping keys to datetime.datetime object and period. For example: {‘date_obj’: datetime.datetime(2015, 6, 1, 0, 0), ‘period’: u’day’}


ValueError - Unknown Language


Period values can be a ‘day’ (default), ‘week’, ‘month’, ‘year’.

Period represents the granularity of date parsed from the given string.

In the example below, since no day information is present, the day is assumed to be current day 16 from current date (which is June 16, 2015, at the moment of writing this). Hence, the level of precision is month:

>>> DateDataParser().get_date_data(u'March 2015')
{'date_obj': datetime.datetime(2015, 3, 16, 0, 0), 'period': u'month'}

Similarly, for date strings with no day and month information present, level of precision is year and day 16 and month 6 are from current_date.

>>> DateDataParser().get_date_data(u'2014')
{'date_obj': datetime.datetime(2014, 6, 16, 0, 0), 'period': u'year'}

Dates with time zone indications or UTC offsets are returned in UTC time unless specified using Settings.

>>> DateDataParser().get_date_data(u'23 March 2000, 1:21 PM CET')
{'date_obj': datetime.datetime(2000, 3, 23, 14, 21), 'period': 'day'}


It fails to parse English dates in the example below, because Spanish was detected and stored with the ddp instance:

>>> ddp.get_date_data('11 August 2012')
{'date_obj': None, 'period': 'day'} can also be initialized with known languages:

>>> ddp = DateDataParser(languages=['de', 'nl'])
>>> ddp.get_date_data(u'vr jan 24, 2014 12:49')
{'date_obj': datetime.datetime(2014, 1, 24, 12, 49), 'period': u'day'}
>>> ddp.get_date_data(u'18.10.14 um 22:56 Uhr')
{'date_obj': datetime.datetime(2014, 10, 18, 22, 56), 'period': u'day'}


dateparser‘s parsing behavior can be configured by supplying settings as a dictionary to settings argument in dateparser.parse or DateDataParser constructor.

All supported settings with their usage examples are given below:

Date Order

DATE_ORDER specifies the order in which date components year, month and day are expected while parsing ambiguous dates. It defaults to MDY which translates to month first, day second and year last order. Characters M, D or Y can be shuffled to meet required order. For example, DMY specifies day first, month second and year last order:

>>> parse('15-12-18 06:00')  # assumes default order: MDY
datetime.datetime(2018, 12, 15, 6, 0)  # since 15 is not a valid value for Month, it is swapped with Day's
>>> parse('15-12-18 06:00', settings={'DATE_ORDER': 'YMD'})
datetime.datetime(2015, 12, 18, 6, 0)

PREFER_LANGUAGE_DATE_ORDER defaults to True. Most languages have a default DATE_ORDER specified for them. For example, for French it is DMY:

>>> # parsing ambiguous date
>>> parse('02-03-2016')  # assumes english language, uses MDY date order
datetime.datetime(2016, 3, 2, 0, 0)
>>> parse('le 02-03-2016')  # detects french, hence, uses DMY date order
datetime.datetime(2016, 3, 2, 0, 0)


There’s no language level default DATE_ORDER associated with en language. That’s why it assumes MDY which is :obj:settings <dateparser.conf.settings> default. If the language has a default DATE_ORDER associated, supplying custom date order will not be applied unless we set PREFER_LANGUAGE_DATE_ORDER to False:

>>> parse('le 02-03-2016', settings={'DATE_ORDER': 'MDY'})
datetime.datetime(2016, 3, 2, 0, 0)  # MDY didn't apply
>>> parse('le 02-03-2016', settings={'DATE_ORDER': 'MDY', 'PREFER_LANGUAGE_DATE_ORDER': False})
datetime.datetime(2016, 2, 3, 0, 0)  # MDY worked!

Handling Incomplete Dates

PREFER_DAY_OF_MONTH This option comes handy when the date string is missing the day part. It defaults to current and can have first and last denoting first and last day of months respectively as values:

>>> from dateparser import parse
>>> parse(u'December 2015')  # default behavior
datetime.datetime(2015, 12, 16, 0, 0)
>>> parse(u'December 2015', settings={'PREFER_DAY_OF_MONTH': 'last'})
datetime.datetime(2015, 12, 31, 0, 0)
>>> parse(u'December 2015', settings={'PREFER_DAY_OF_MONTH': 'first'})
datetime.datetime(2015, 12, 1, 0, 0)

PREFER_DATES_FROM defaults to current_period and can have past and future as values.

If date string is missing some part, this option ensures consistent results depending on the past or future preference, for example, assuming current date is June 16, 2015:

>>> from dateparser import parse
>>> parse(u'March')
datetime.datetime(2015, 3, 16, 0, 0)
>>> parse(u'March', settings={'PREFER_DATES_FROM': 'future'})
datetime.datetime(2016, 3, 16, 0, 0)
>>> # parsing with preference set for 'past'
>>> parse('August', settings={'PREFER_DATES_FROM': 'past'})
datetime.datetime(2015, 8, 15, 0, 0)

RELATIVE_BASE allows setting the base datetime to use for interpreting partial or relative date strings. Defaults to the current date and time.

For example, assuming current date is June 16, 2015:

>>> from dateparser import parse
>>> parse(u'14:30')
datetime.datetime(2015, 3, 16, 14, 30)
>>> parse(u'14:30', settings={'RELATIVE_BASE': datetime.datetime(2020, 1, 1)})
datetime.datetime(2020, 1, 1, 14, 30)
>>> parse(u'tomorrow', settings={'RELATIVE_BASE': datetime.datetime(2020, 1, 1)})
datetime.datetime(2020, 1, 2, 0, 0)

STRICT_PARSING defaults to False.

When set to True if missing any of day, month or year parts, it does not return any result altogether.:

>>> parse(u'March', settings={'STRICT_PARSING': True})

Language Detection

SKIP_TOKENS is a list of tokens to discard while detecting language. Defaults to ['t'] which skips T in iso format datetime string .e.g. 2015-05-02T10:20:19+0000.:

>>> from import DateDataParser
>>> DateDataParser(settings={'SKIP_TOKENS': ['de']}).get_date_data(u'27 Haziran 1981 de')  # Turkish (at 27 June 1981)
{'date_obj': datetime.datetime(1981, 6, 27, 0, 0), 'period': 'day'}