Usual number of days in your period:

11 / 2016

MonTueWedThuFriSatSun
  1 2 3 4 5 6
7 8 9 10 11 12 13
14 15 16 17 18 19 20
21 22 23 24 25 26 27
28 29 30        

12 / 2016

MonTueWedThuFriSatSun
      1 2 3 4
5 6 7 8 9 10 11
12 13 14 15 16 17 18
19 20 21 22 23 24 25
26 27 28 29 30 31  

1 / 2017

MonTueWedThuFriSatSun
            1
2 3 4 5 6 7 8
9 10 11 12 13 14 15
16 17 18 19 20 21 22
23 24 25 26 27 28 29
30 31          

Click on a date on the calendar to mark the first day of your last period.

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