Python parser for human readable dates
Key Features • How To Use • Installation • Common use cases • You may also like... • License
- Support for almost every existing date format: absolute dates,
relative dates (
"two weeks ago"or"tomorrow"), timestamps, etc. - Support for more than 200 language locales.
- Language autodetection
- Customizable behavior through settings.
- Support for non-Gregorian calendar systems.
- Support for dates with timezones abbreviations or UTC offsets
(
"August 14, 2015 EST","21 July 2013 10:15 pm +0500"...) - Search dates in longer texts.
- Time span detection for expressions like "past month", "last week".
Do you want to try it out without installing any dependency? Now you can test it quickly by visiting this online demo!
The most straightforward way to parse dates with dateparser is to
use the dateparser.parse() function, that wraps around most of the
functionality of the module.
>>> import dateparser >>> dateparser.parse('Fri, 12 Dec 2014 10:55:50') datetime.datetime(2014, 12, 12, 10, 55, 50) >>> dateparser.parse('1991-05-17') datetime.datetime(1991, 5, 17, 0, 0) >>> dateparser.parse('In two months') # today is 1st Aug 2020 datetime.datetime(2020, 10, 1, 11, 12, 27, 764201) >>> dateparser.parse('1484823450') # timestamp datetime.datetime(2017, 1, 19, 10, 57, 30) >>> dateparser.parse('January 12, 2012 10:00 PM EST') datetime.datetime(2012, 1, 12, 22, 0, tzinfo=<StaticTzInfo 'EST'>)
dateparser also works with strings in different languages:
>>> dateparser.parse('Martes 21 de Octubre de 2014') # Spanish (Tuesday 21 October 2014) datetime.datetime(2014, 10, 21, 0, 0) >>> dateparser.parse('Le 11 Décembre 2014 à 09:00') # French (11 December 2014 at 09:00) datetime.datetime(2014, 12, 11, 9, 0) >>> dateparser.parse('13 января 2015 г. в 13:34') # Russian (13 January 2015 at 13:34) datetime.datetime(2015, 1, 13, 13, 34) >>> dateparser.parse('1 เดือนตุลาคม 2005, 1:00 AM') # Thai (1 October 2005, 1:00 AM) datetime.datetime(2005, 10, 1, 1, 0) >>> dateparser.parse('yaklaşık 23 saat önce') # Turkish (23 hours ago), current time: 12:46 datetime.datetime(2019, 9, 7, 13, 46) >>> dateparser.parse('2小时前') # Chinese (2 hours ago), current time: 22:30 datetime.datetime(2018, 5, 31, 20, 30)
You can specify the language(s), if known, using the languages argument.
In this case, given languages are used and language detection is skipped:
>>> dateparser.parse('2015, Ago 15, 1:08 pm', languages=['pt', 'es']) datetime.datetime(2015, 8, 15, 13, 8)
If you know the possible formats of the dates, you can use the
date_formats argument:
>>> dateparser.parse('22 Décembre 2010', date_formats=['%d %B %Y']) datetime.datetime(2010, 12, 22, 0, 0)
The formats are tried first. A date string that none of them parses is then
parsed as if no formats were given, so a number that is out of range for a
format can be read as another part of the date (32 is not a day, but it is
a valid two-digit year). To accept only the given formats, set PARSERS to
['custom-formats'], which also turns off timestamps, relative dates and
free-form dates:
>>> dateparser.parse('32 DEC 10', date_formats=['%d %b %y']) datetime.datetime(2032, 12, 10, 0, 0) >>> dateparser.parse('32 DEC 10', date_formats=['%d %b %y'], settings={'PARSERS': ['custom-formats']}) None
>>> from dateparser import parse >>> parse('1 hour ago') datetime.datetime(2015, 5, 31, 23, 0) >>> parse('Il ya 2 heures') # French (2 hours ago) datetime.datetime(2015, 5, 31, 22, 0) >>> parse('1 anno 2 mesi') # Italian (1 year 2 months) datetime.datetime(2014, 4, 1, 0, 0) >>> parse('yaklaşık 23 saat önce') # Turkish (23 hours ago) datetime.datetime(2015, 5, 31, 1, 0) >>> parse('Hace una semana') # Spanish (a week ago) datetime.datetime(2015, 5, 25, 0, 0) >>> parse('2小时前') # Chinese (2 hours ago) datetime.datetime(2015, 5, 31, 22, 0) >>> parse('next Wednesday') datetime.datetime(2015, 6, 3, 0, 0)
In English, last, this and next before a weekday mean its closest
occurrence before, on or after, and after the current date, respectively,
regardless of the PREFER_DATES_FROM setting. So this Wednesday and
next Wednesday are the same date except on a Wednesday. They do not apply
to wed, sat and sun, which are also common English words.
Note
Testing above code might return different values depending on your environment's current date and time.
Note
For the Finnish language, please specify settings={'SKIP_TOKENS': []} to correctly parse relative dates.
>>> # parsing ambiguous date >>> parse('02-03-2016') # assumes english language, uses MDY date order datetime.datetime(2016, 2, 3, 0, 0) >>> parse('le 02-03-2016') # detects french, uses DMY date order datetime.datetime(2016, 3, 2, 0, 0)
Note
Ordering is not locale-based — do not expect DMY order for UK/Australia English.
You can specify date order explicitly:
>>> parse('18-12-15 06:00', settings={'DATE_ORDER': 'DMY'}) datetime.datetime(2015, 12, 18, 6, 0)
For more on date order, see the settings documentation.
By default, dateparser returns a timezone-aware datetime if a timezone is
present in the date string. Otherwise it returns a naive datetime object.
>>> parse('January 12, 2012 10:00 PM EST') datetime.datetime(2012, 1, 12, 22, 0, tzinfo=<StaticTzInfo 'EST'>) >>> parse('January 12, 2012 10:00 PM -0500') datetime.datetime(2012, 1, 12, 22, 0, tzinfo=<StaticTzInfo 'UTC\-05:00'>) >>> parse('2 hours ago EST') datetime.datetime(2017, 3, 10, 15, 55, 39, 579667, tzinfo=<StaticTzInfo 'EST'>)
If the date has no timezone name/abbreviation or offset, you can specify it
using the TIMEZONE setting:
>>> parse('January 12, 2012 10:00 PM', settings={'TIMEZONE': 'US/Eastern'}) datetime.datetime(2012, 1, 12, 22, 0) >>> parse('January 12, 2012 10:00 PM', settings={'TIMEZONE': 'US/Eastern', 'RETURN_AS_TIMEZONE_AWARE': True}) datetime.datetime(2012, 1, 12, 22, 0, tzinfo=<DstTzInfo 'US/Eastern' EST-1 day, 19:00:00 STD>) >>> parse('10:00 am', settings={'TIMEZONE': 'EST', 'TO_TIMEZONE': 'EDT'}) datetime.datetime(2016, 9, 25, 11, 0) >>> parse('10:00 am EST', settings={'TO_TIMEZONE': 'EDT'}) datetime.datetime(2017, 3, 12, 11, 0, tzinfo=<StaticTzInfo 'EDT'>)
For more on timezones, see the settings documentation.
>>> from dateparser import parse >>> parse('December 2015') # default behavior datetime.datetime(2015, 12, 16, 0, 0) >>> parse('December 2015', settings={'PREFER_DAY_OF_MONTH': 'last'}) datetime.datetime(2015, 12, 31, 0, 0) >>> parse('December 2015', settings={'PREFER_DAY_OF_MONTH': 'first'}) datetime.datetime(2015, 12, 1, 0, 0) >>> parse('March') datetime.datetime(2015, 3, 16, 0, 0) >>> parse('March', settings={'PREFER_DATES_FROM': 'future'}) datetime.datetime(2016, 3, 16, 0, 0) >>> import dateparser >>> dateparser.parse("2015") # default behavior datetime.datetime(2015, 3, 27, 0, 0) >>> dateparser.parse("2015", settings={"PREFER_MONTH_OF_YEAR": "last"}) datetime.datetime(2015, 12, 27, 0, 0) >>> dateparser.parse("2015", settings={"PREFER_MONTH_OF_YEAR": "current"}) datetime.datetime(2015, 3, 27, 0, 0)
You can also ignore incomplete dates by setting the STRICT_PARSING flag:
>>> parse('December 2015', settings={'STRICT_PARSING': True}) None
For more on handling incomplete dates, see the settings documentation.
Warning
Support for date searching is limited and needs improvement. Contributions are welcome — see contributing.
You can extract dates from longer strings of text. Results are returned as a
list of (substring, datetime) tuples:
>>> from dateparser.search import search_dates >>> search_dates('Today is 25 of October 2017, so the 27th is in 2 days.') [('25 of October 2017', datetime.datetime(2017, 10, 25, 0, 0)), ('the 27th is in 2 days', datetime.datetime(2017, 10, 27, 0, 0))]
Pass languages when you know them: language detection is slow and
error-prone on short text. If no date is found, None is returned:
>>> search_dates('Lancé le 4 octobre 1957.', languages=['fr']) [('le 4 octobre 1957', datetime.datetime(1957, 10, 4, 0, 0))] >>> search_dates('Rien à voir.', languages=['fr']) None
See the API reference
for other parameters, such as strategy.
The search_dates function can also detect time spans such as "past month"
or "last week". When RETURN_TIME_SPAN is enabled it returns start and end
dates for the detected period.
For example, assuming the current date and time is December 7, 2024, 15:30:
>>> search_dates("Messages from the past month", settings={'RETURN_TIME_SPAN': True}) [('past month (start)', datetime.datetime(2024, 11, 7, 15, 30)), ('past month (end)', datetime.datetime(2024, 12, 7, 15, 30))]
You can control multiple behaviors by using the settings parameter:
>>> dateparser.parse('2014-10-12', settings={'DATE_ORDER': 'YMD'}) datetime.datetime(2014, 10, 12, 0, 0) >>> dateparser.parse('2014-10-12', settings={'DATE_ORDER': 'YDM'}) datetime.datetime(2014, 12, 10, 0, 0) >>> dateparser.parse('1 year', settings={'PREFER_DATES_FROM': 'future'}) # Today is 2020-09-23 datetime.datetime(2021, 9, 23, 0, 0) >>> dateparser.parse('tomorrow', settings={'RELATIVE_BASE': datetime.datetime(1992, 1, 1)}) datetime.datetime(1992, 1, 2, 0, 0)
To see all available settings, check the settings documentation.
dateparser will do its best to return a date, dealing with multiple formats and different locales. For that reason it is important that the input is a valid date, otherwise it could return false positives.
To reduce the possibility of receiving false positives, make sure that:
- The input string is a valid date and doesn't contain any other words or numbers.
- If you know the language or languages beforehand, you add them through the
languagesorlocalesproperties.
On the other hand, if you want to exclude any of the default parsers
(timestamp, relative-time...) or change the order in which they
are executed, you can do so through the
settings PARSERS.
Dateparser supports Python 3.10+. You can install it by doing:
$ pip install dateparser
If you want to use a non-Gregorian calendar, you need to install the
calendars extra:
$ pip install dateparser[calendars]
Apart from the Gregorian calendar, dateparser supports the Persian Jalali
calendar, the Hijri/Islamic calendar, the French Republican calendar and
the Minguo calendar. To use the first three, install the calendars extra
(see Installation).
Example using the Persian Jalali calendar:
>>> from dateparser.calendars.jalali import JalaliCalendar >>> JalaliCalendar('جمعه سی ام اسفند ۱۳۸۷').get_date() DateData(date_obj=datetime.datetime(2009, 3, 20, 0, 0), period='day', locale=None, parts=('year', 'month', 'day'))
Example using the Hijri/Islamic calendar:
>>> from dateparser.calendars.hijri import HijriCalendar >>> HijriCalendar('17-01-1437 هـ 08:30 مساءً').get_date() DateData(date_obj=datetime.datetime(2015, 10, 30, 20, 30), period='day', locale=None, parts=('year', 'month', 'day', 'time'))
Example using the French Republican calendar:
>>> from dateparser.calendars.french_republican import FrenchRepublicanCalendar >>> FrenchRepublicanCalendar('18 brumaire an VIII').get_date() DateData(date_obj=datetime.datetime(1799, 11, 9, 0, 0), period='day', locale=None)
Example using the Minguo calendar:
>>> from dateparser.calendars.minguo import MinguoCalendar >>> MinguoCalendar('民國101年5月25日 08:36').get_date() DateData(date_obj=datetime.datetime(2012, 5, 25, 8, 36), period='day', locale=None)
dateparser relies on the following libraries:
- dateutil's module
relativedeltafor its freshness parser. - convertdate to convert Jalali and French Republican dates to Gregorian.
- hijridate to convert Hijri dates to Gregorian.
- tzlocal to reliably get local timezone.
- ruamel.yaml (optional) for operations on language files.
dateparser can be used for a wide variety of purposes, but it stands out when it comes to:
- Scraping: extract dates from different places with several different formats and languages
- IoT: consuming data coming from different sources with different date formats
- Tooling: consuming dates from different logs / sources
- Format transformations: when transforming dates coming from different files (PDF, CSV, etc.) to other formats (database, etc).
- Tooling and CLI: allow users to write “3 days ago” to retrieve information.
- Search engine: allow people to search by date in an easy / natural format.
- Bots: allow users to interact with a bot easily
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