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What date was 1 month ago?

Wed, September 2, 2026

What date was 1 month ago — Wed, September 2, 2026. That is a Wednesday, day 245 of the year, in ISO week 36. It is counted from Fri, October 2, 2026 in calendar months, so a date the target month does not have falls back to its last day. 120 days remain in the year after it. Public holidays are not deducted, because which ones apply depends on where you are.

Counted today, · How we check

Counted from Fri, October 2, 2026 in US Eastern time, in calendar months. A date the target month does not have falls back to its last day, which is what a contract means by the same span.

Days that turned out to be
-30, because months are not equal lengths
Weekday
Wednesday
ISO week
Week 36
Day of the year
245 of 365
Left in the year
120 days

Change the number

The same calculator, opened on this question. Switch between calendar and business days to see the two answers a contract can mean.

Date
Wed, September 2, 2026
Days counted
30 * (1 + 7 * 0)30 days
Calendar days a business count covers
7 * 6 + 0 + 042 days
Counting every day
2026-10-02 + -1 * 30Wed, September 2, 2026
Counting Monday to Friday only
20728 + -1 * 42Fri, August 21, 2026
Date
2026-09-02 * 1 + 2026-08-21 * 0Wed, September 2, 2026
Difference between the two counts
abs(2026-09-02 - 2026-08-21)12 days
That span in weeks
abs(2026-09-02 - 2026-10-02) / 74.286 weeks

Other spans

Related

Questions people actually ask

Why does my own count of 1 month ago come out a day different?
Because a span can be counted inclusively or exclusively and neither is wrong. This page counts the days between the two dates and no more: Fri, October 2, 2026 is day zero, not day one, so -30 days on lands on Wed, September 2, 2026. Count the starting day as well — the way a hotel counts nights against days, or a contract that says "within N days including the day of service" — and you land one day earlier. Read the wording before trusting either.
Are weekends and public holidays counted?
Both are counted here. Every day is a day. One marked day falls inside this span (Labor Day), and none of them changes the count. A public holiday is never deducted automatically, because which ones apply depends on where you are.
Which day does this count from?
Fri, October 2, 2026, in US Eastern time. The page is regenerated hourly, so around midnight it can be a few hours behind your own date if you are in another zone — the answer is stated rather than assumed, which is the point of printing the starting day at all.

Sources