How to find one month later from a date with django?

Question

I want to find one month later from a date but I don't know how.

Lets say I have this date:

08.03.2012

I want to find one month later from that date automatically like:

08.04.2012

Does anyone know how to do that?

some months have 31 days some have 30 days and february has 28 days so i want to know if django can calculate it automatically — Eren Süleymanoğlu, Mar 08 '12 at 21:26
@Eren: This is not really clear. What's one month after the `31.1`, for example? — Niklas B., Mar 08 '12 at 21:33
@NiklasB. one month after january 31, would be the last day of february. See paolo's explanation. — Chris, Feb 09 '13 at 15:13
I vote for reopen because helps people to find an answer for one more late in django. — dani herrera, Mar 19 '21 at 06:20

score 43 · Accepted Answer · answered Mar 08 '12 at 21:32

43

With dateutil:

>>> import datetime
>>> d1 = datetime.date.today()
>>> from dateutil.relativedelta import relativedelta
>>> d1 + relativedelta(months=1)
datetime.date(2012, 4, 8)

>>> d2 = datetime.date(year=2012,month=1,day=31)
>>> d2 + relativedelta(months=1)
datetime.date(2012, 2, 29)

answered Mar 08 '12 at 21:32

dani herrera

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you also need to install python-dateutil to use this. – Marius Grigaitis Mar 08 '12 at 21:41
@marltu, you are right. Here [dateutil doc](http://labix.org/python-dateutil). Installed by default with python Ubuntu install. I don't know about other linux or windows distributions. – dani herrera Mar 08 '12 at 22:03

score 2 · Answer 2 · edited Feb 20 '17 at 06:26

As Niklas commented, since months vary in length, one month from today can be pretty ambiguous.

Every industry has some sort of convention; the result may be different depending on your goals. For example, will it be used for interest calculations? will it be used to generate recurrent bills?

If you want 30 days from today:

>>> import datetime
>>> d1 = datetime.date.today()
>>> d1
datetime.date(2012, 3, 8)
>>> d1 + datetime.timedelta(30)
datetime.date(2012, 4, 7)

May not be what you want if month has 31 days:

>>> d2 = datetime.date(2012, 1, 1)
>>> d2 + datetime.timedelta(30)
datetime.date(2012, 1, 31)
>>> import calendar
>>> calendar.monthrange(2012, 1)
(6, 31)
>>> d2 + datetime.timedelta(calendar.monthrange(d2.year, d2.month)[1])
datetime.date(2012, 2, 1)

Yet, may not be the result you expect if next month has less than 30 days:

>>> d3 = datetime.date(2012, 1, 31)
>>> d3 + datetime.timedelta(calendar.monthrange(d3.year, d3.month)[1])
datetime.date(2012, 3, 2)
>>> import dateutil
>>> d3 + dateutil.relativedelta.relativedelta(months=1)
datetime.date(2012, 2, 29)

score 0 · Answer 3 · edited May 26 '12 at 15:32

0

If you are using the datetime filed, you can pull out the month add it and then set it back.

such as:

d = datetime.date(2003, 7, 29)
d=d.month+1

of course i am still confused on how date time works if your not a delimiter using ["."] would be your best bet

edited May 26 '12 at 15:32

Martijn Pieters

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answered Mar 08 '12 at 21:31

EdgarAllenBro

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This won't work for dates like 12/1/2014 which will wrap the year. – Ben Liyanage Dec 25 '14 at 00:14

How to find one month later from a date with django?

3 Answers3