Date → week number

September 3, 1971: What week number?

Friday, September 3, 1971ISO Week 351971-W35

ISO Week 35 runs from August 30, 1971 to September 5, 1971.

Mon30AugustTue31AugustWed1SeptemberThu2SeptemberFri3SeptemberSat4SeptemberSun5September
← 09-02-197109-04-1971 →

ISO vs US-style week numbers

The same date can have different week numbers

ISO weeks start on Monday. The simplified US-style system starts on Sunday and counts the week containing January 1 as Week 1.

ISO week1971-W35

August 30 – September 5, 1971

MonTueWedThuFriSatSun
Week 1 contains the first Thursday of the year.ISO guide →
US-style weekWeek 36

August 29 – September 4, 1971

SunMonTueWedThuFriSat
Week 1 contains January 1.US-style guide →
ISO weekWeek 35
US-style weekWeek 36
WeekdayFriday
QuarterQ3
Day of year246 / 365
ISO weekday5 / 7

Date context

Friday, September 3, 1971 is day 246 of 1971 and belongs to ISO Week 35.

This ISO week crosses a month boundary: it starts in August and ends in September.

Distance from today

How long ago was September 3, 1971?

Days20072
Full weeks2867
Remaining days3

September 3, 1971 is 20072 days before today, equal to 2867 full weeks and 3 days.