Add days to a date
This calculator finds the date a number of days, weeks, months, years or business days after or before any date. Use it for deadlines, notice periods, warranty and return windows, visa stays, due dates and follow-up appointments. For the date counted from today, the quick pages are faster: 30 days from today, 60 days from today, 90 days from today and 180 days from today.
Days from common start dates in 2026
| Start date | +30 days | +45 days | +60 days | +90 days | +120 days | +180 days |
|---|---|---|---|---|---|---|
| Jan 1, 2026 | Jan 31 | Feb 15 | Mar 2 | Apr 1 | May 1 | Jun 30 |
| Apr 1, 2026 | May 1 | May 16 | May 31 | Jun 30 | Jul 30 | Sep 28 |
| Jul 1, 2026 | Jul 31 | Aug 15 | Aug 30 | Sep 29 | Oct 29 | Dec 28 |
| Oct 1, 2026 | Oct 31 | Nov 15 | Nov 30 | Dec 30 | Jan 29 | Mar 30 |
Days, weeks or months?
Days and weeks are exact: a week is always 7 days, so 6 weeks from a date is the same as 42 days. Months are not: 3 months from January 31 is not the same as 90 days. When a contract or law says “90 days”, count days; when it says “3 months”, count months. For working-day rules, count business days.
In Excel or Google Sheets
Put the start date in A1. Use =A1+90 to add 90 days, =A1-90 to go back, =EDATE(A1,3) to add 3 months and =WORKDAY(A1,10) to add 10 business days. Format the result as a date.
To count the days between two dates instead, use the date duration calculator. To count down to a date, use days until.
Frequently asked questions
How do I add days to a date?
Pick the start date, choose Add, type the number of days and keep the unit on Days. The result is the date that many calendar days later, not counting the start date itself. For example, 1 day after Monday is Tuesday.
What is 90 days from a date?
Add 90 calendar days. From October 13, 2026 that is Monday, January 11, 2027. Ninety days is about three months but not exactly, because months have 28 to 31 days.
How do I subtract days from a date?
Choose Subtract instead of Add. The calculator counts backwards, so 30 days before March 31 is March 1 (or March 2 in a leap year).
Does the count include the start date?
No. The start date is day 0. If your rule counts the start date as day 1, as some visa and notice-period rules do, take one day off the answer.
How are months added?
A month is added by keeping the same day number, so one month after January 15 is February 15. If that day does not exist, such as one month after January 31, the result moves into the next month.
How do I add business days?
Choose Business days. Saturdays and Sundays are skipped; public holidays are not, so add a day for each holiday in between.
Is the Date Calculator (Add Days to a Date) free to use?
Yes. The Date Calculator (Add Days to a Date) is free, with no sign-up and no limit on how often you use it.
Does the Date Calculator (Add Days to a Date) work on a mobile phone?
Yes. It works in any modern browser on Android, iPhone, tablets and computers. You can also add Countdown Converter to your home screen like an app.