Ninety days: a quarter-length plan
The page adds ninety days to the date your device shows and prints the result in full, with the weekday and ISO week number. It also shows the date ninety days in the past, handy for looking back over the same span.
Ninety days is the shape of a quarter. Teams use it for a three-month plan, a first-hundred-days style goal, a long habit experiment, or a trial of a tool or subscription that is quoted in days. Whatever the context, this gives you the date to enter in a calendar.
It is close to three months but rarely exactly three. From 1 January to 1 April is 90 days, yet from 1 June, ninety days ends on 30 August, two days before 1 September. If the same date three months on is what you want, use the date calculator with 3 months.
The result is 12 weeks and 6 days away, so the weekday lands one day before today's weekday. Start on a Tuesday and you finish on a Monday, which can be a useful trick when you want a deadline at the start of a working week.
Worked examples
Questions about this tool
Is 90 days the same as three months?
Sometimes, but not reliably. Three months can run from 89 to 92 days. This page counts exactly 90.
Which weekday will 90 days from today be?
One weekday before today's weekday, because 90 days is 12 weeks plus 6 days.
Can I find the date 90 days before a future event?
Use the date calculator, enter the event date and subtract 90 days.