Find the weekday of any date, with ISO weekday number, day of year, ISO week and the first weekday of the month. Free online date calculator. All processing runs locally in your browser. Your data is not uploaded to any server.
100% Local Processing
How to Use
Pick any date and get its weekday, by name and by ISO number, plus its position in the year and the month around it.
Steps
Pick the date you are interested in.
Click Calculate.
Read the weekday, ISO day number, week number and month context.
What the result shows
The weekday by name, such as Saturday.
The ISO weekday number, where Monday is 1 and Sunday is 7.
The day of the year and the ISO week number.
The weekday of the first and last day of that month.
Features
Exactly follows the ISO 8601 weekday numbering.
Month boundaries are correct for the year you pick.
Calculations run locally with nothing uploaded.
All processing runs locally in your browser. Your data is not uploaded to any server.