Instructions
Month calendar
How to use
Move between months and press a date. The week can start on Monday.
Move between months and press a date. The week can start on Monday.
Supported input
Week numbers follow ISO 8601: weeks start on Monday and week 1 has the year's first Thursday.
Input example
2026-12-25
Result example
Friday · week 52 · D-73
Troubleshooting
If it stops responding, reload the page. If there is no sound, check the device volume and silent mode.
Limitations
Public holidays and lunar dates are not shown. Nothing is saved.
How it works
A month calendar that shows a date's weekday, week number, distance from today and day of the year. Week numbers follow ISO 8601: weeks start on Monday and week 1 has the year's first Thursday.
Units & precision
Week numbers follow ISO 8601: weeks start on Monday and week 1 has the year's first Thursday.