OnlyWeekNo. vs DayNumCalc Usage & Stats
You can choose the first day of the week, like starting with Sunday or Monday?
And you can also choose a rule for the first week of the year. Like ISO 8601, you can choose the first Thursday week as the 1st week, or January 1st as the 1st week, or else.
- Apple App Store
- Free
- Utilities
Store Rank
- -
DayNumCalc gives easy access to basic date calculations:
- The current date/day number information is immediately available. Examples: day 1 = 1 January; day 365 = 31 December (non-leap year) or 30 December (leap year)
- Date/day number calculations: get the day number from a chosen date, and a date from a paired year/day number
- Calculate the number of days between two dates
- Determine a date after adding or subtracting a number of days fro a chosen date
- Check the day of the week for a date of your choice
Widgets for the Home Screen, the Today View, and the Lock Screen are available for ease of use.
- Apple App Store
- Paid
- Utilities
Store Rank
- -
OnlyWeekNo. VS. 
DayNumCalcJanuary 18, 2026