Day Calculator is an app that allows you to easily calculate dates and days. You can easily check dates such as anniversaries because you can calculate the number of days from the date or the date from the number of days. You can also specify whether to include the start date or not. ・Calculate the number of days from a date You can calculate the number of days between start and end dates. In addition to notation by year, month and day, it is also displayed by month and day, or day only. ・Calculate date by date + number of days You can easily see the date after a certain number of days from the start date and number of days. ・Calculate date with date - number of days From the start date and number of days, you can easily check the previous date for that number of days. ・ Calculate the number of days from today on X day If you enter the date, you can check how many days from today that date is. It is also displayed in year, month, day, month and day, or day only. ・Calculate how many days ago from today If you enter the date, you can check how many days ago that day is from today. It is also displayed in year, month, day, month and day, or day only.