MonthSprig treats calendar dates as year, month and day values. They do not pass through a time-zone conversion. The supported range is 1900–2100, and the first weekday changes the arrangement of the grid rather than the meaning of a date.

Use dates within the supported range

Select a year from 1900 through 2100. The selected month, event dates and full requested range must use valid dates inside that span. For an academic calendar or week near an edge of the range, check its last date as well as its first. A twelve-month range cannot continue beyond the supported final year.

If a field reports a range error, correct that field and review the result. Your original input should stay visible while the error is explained. Do not replace an invalid date with the nearest valid one unless that is actually the date you intended to enter.

Use an unambiguous date format

For CSV and text date entry, use YYYY-MM-DD. For example, 2027-03-08 means March 8, 2027. Include both digits for the month and day. A value such as 03/04/2027 is ambiguous and needs correction; MonthSprig does not guess which regional convention you meant.

Date fields must also describe a real day. February 29, 2027 is not valid, while February 29, 2028 is. A date with month 13 or day 32 is not repaired silently. Check the source of the date, enter the intended value and confirm that the preview now places it correctly.

Check leap-year behavior

The Gregorian leap-year rule gives February an extra day in qualifying years. In the supported range, 1900 is not a leap year, 2000 is a leap year and 2028 is a leap year. The calendar grid follows that rule; the number of days is not determined by a visual template.

An annual event on February 29 keeps that month-and-day rule. It appears in a year containing February 29 and is skipped in a year that does not. If you intend a different date in a non-leap year, add the actual date you want instead of expecting a silent shift.

Choose Monday or Sunday

Use the week-start setting to choose Monday or Sunday. The weekday headings and date positions change together. Existing events remain attached to their dates. After changing the setting, inspect a longer event and the first and final rows of the month.

The number of rows can change. November 2026 needs six rows with Monday first and five with Sunday first. All thirty dates must remain visible in either arrangement. A sixth row is part of the calendar, not an error or an extra page that should be removed.

Check the output after a date change

Read the month and year title, then the first and last dates. For a week or academic range, inspect the dates around the change of month or year. Check repeated events again if their available occurrences have changed with the selected range.

Download a fresh file after changing dates or week start. A PDF already on your device does not update when you edit the project. Use a clear file name and keep a JSON project backup if you will need to revisit the arrangement later.