Day Countdown Calculator

Count the days until any future date — or find how many days have passed since a past date. Enter a day, month, and year and get the result instantly in days, weeks, and months.

Target Date

How to Count Days Until a Date

Enter the day, month, and year of your target date. The result appears instantly — no button needed.

Example: If today is 16 May 2026 and your target date is 25 December 2026:

  • Days until: 223
  • Weeks until: 31
  • Months until: 7

Past Dates — Days Since

If the target date is in the past, the calculator shows how long ago it was, labelled as “days ago”.

Example: If today is 16 May 2026 and your target date is 1 January 2026:

  • Days ago: 135
  • Weeks ago: 19
  • Months ago: 4

How Weeks and Months Are Calculated

FormulaExample (100 days)
Weeksdays ÷ 7, rounded down14
Monthsdays ÷ 30.44, rounded down3

30.44 is the average number of days per month across a calendar year (365.25 ÷ 12).

Common Use Cases

  • Counting down to a holiday, trip, exam, or project deadline
  • Finding how many days since a past event (launch, anniversary, start date)
  • Planning and scheduling — how many weeks until a milestone?
  • Tracking elapsed time since a specific date

Frequently Asked Questions

How do I count the days until a date?

Enter the day, month, and year of your target date. The calculator instantly shows how many days away it is, plus the equivalent in weeks and months.

What happens if I enter a past date?

The calculator shows how many days have passed since that date — displayed as 'X days ago'. Weeks and months are also shown. No error is shown for past dates.

How are weeks and months calculated?

Weeks = days ÷ 7 (rounded down). Months = days ÷ 30.44 (rounded down), where 30.44 is the average number of days in a month across a year.

What does 'Today is the day!' mean?

It means the date you entered is today. The day count shows 0 and the note appears to confirm it.

What is the difference between this and the birthday countdown?

The birthday countdown repeats every year — it always finds the next upcoming occurrence of a date. This calculator is for any single specific date, including past dates, and does not repeat annually.