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A lightweight Dart package which provides the class Week (based on the local time). Instances represent specific weeks spanning Monday to Sunday. An ISO week-numbering year has 52 or 53 full weeks. Week 1 is defined to be the first week with 4 or more days in January.

It’s called isoweek because this is the week definition of ISO 8601. This package is inspired by the isoweek Python package.


import 'package:isoweek/isoweek.dart';

void main() {
  Week currentWeek = Week.current();
  print('Current week: $currentWeek');
  //OUTPUT: 2021W13

  print('Days of current week: ${currentWeek.days}');
  //OUTPUT: [2021-03-29 00:00:00.000, 2021-03-30 00:00:00.000, ...]

  Week nextWeek =;
  print('Days of next week: ${nextWeek.days}');
  //OUTPUT: Days of next week: [2021-04-05 00:00:00.000, 2021-04-06 00:00:00.000, ...]

  Week previousWeek = currentWeek.previous;
  print('Days of previous week: ${previousWeek.days}');
  //OUTPUT: Days of previous week: [2021-03-22 00:00:00.000, 2021-03-23 00:00:00.000, ...]

  Week futureWeek = currentWeek.addWeeks(5);
  print('5 weeks ahead: $futureWeek');
  //OUTPUT: 5 weeks ahead: 2021W18

  Week birthdayWeek = Week.fromDate(DateTime(2020, 11, 16));
      'The week number of my birthday in 2020 was ${birthdayWeek.weekNumber}');
  //OUTPUT: The week number of my birthday in 2020 was 47

  Week weekFromIso = Week.fromISOString('2021W25');
  print('Week from ISO string: $weekFromIso');
  //OUTPUT: Week from ISO: 2021W25

  DateTime firstDay =;
  print('The Week $weekFromIso starts with $firstDay');
  //OUTPUT: The Week 2021W25 starts with 2021-06-21 00:00:00.000