How it works
Pick a target date and an optional start date. The calculator counts whole days between them and shows the total in days, weeks and months.
Tips
- Use it for exams, trips, anniversaries, deadlines and releases.
- Leave the from date as today to count down from now.
- Past dates are shown as D+n, future dates as D-n.
Standards and sources
- Whole-day difference between two dates
- Calendar parts use standard month and year lengths
- For reference only
Last reviewed October 8, 2026
Frequently asked questions
How are the days counted?
Whole days between the from date and the target date, not counting the first day. If the target is in the past, the same count is shown as days since.
What does D-Day mean?
D-Day is the target day itself. Dates ahead are shown as D-n and dates that have passed as D+n, as in a military or exam countdown.
Can I count from a different start date?
Yes. The from date defaults to today but you can set any date, so it also works for anniversaries and deadlines.