How to use
- Pick a mode from the tabs at the top: Countdown / Days Between / Add-Subtract Days.
- Countdown: choose a target date and hit Calculate. You'll see how many days remain (or have passed), the weekday of the target, the count in weeks and days, and an approximate month conversion.
- Days Between: enter two dates and decide whether the start date should count as a day. The result shows the total days plus week, month, and year equivalents.
- Add/Subtract Days: enter a base date and a number of days (negative numbers go backward). Handy for questions like "what date is 90 days from today?" — you get the exact date and its weekday.
How the countdown works
The calculator normalizes both dates to midnight, takes the difference in milliseconds, and divides by the length of one day (86,400,000 ms). Time of day is ignored entirely, so the result never changes depending on when you check it during the day.
| Result | Meaning |
|---|---|
| 7 days left | The event is one week away |
| 1 day left | The event is tomorrow |
| Today is the day | The target date is today |
| 1 day ago | The event was yesterday |
Counting conventions: inclusive vs. exclusive
The same pair of dates can honestly produce two different answers, depending on whether the first day counts. Measured as a gap, today through tomorrow is 1 day; counted inclusively — where the first day is itself a full day — it's 2 days. Neither is wrong; they answer different questions. Legal deadlines, rental agreements, and prescriptions each follow their own convention, so it's worth checking which one applies before you rely on a number.
| Convention | Today → tomorrow | Typical uses |
|---|---|---|
| Exclusive (start date not counted) | 1 day | Date gaps, countdowns, hotel nights |
| Inclusive (start date counted) | 2 days | Workdays billed, medication courses, full trip length |
Week, month, and year conversions
Weeks are exact: the day count divided by 7, with the remainder shown as leftover days. Months and years can't be exact because calendar months vary in length, so the calculator uses averages — one month ≈ 30.44 days (365.25 ÷ 12) and one year ≈ 365.25 days — and labels those figures as approximate.
Good to know
- Exam prep: set your test date as the target and note the 100-, 50-, and 30-day marks to break your study plan into phases.
- Once the date passes, the countdown automatically flips to "days ago" — useful for tracking how long a project, streak, or habit has been running.
- Contract and refund windows: in Add/Subtract mode, enter the signing date plus 14 or 30 days to see exactly when a window closes — and whether that day lands on a weekend.
- Pregnancy, visas, and billing cycles all boil down to date arithmetic: due dates are typically 280 days from a start date, many visa rules cap stays at 90 days within a 180-day window, and both are one Add/Subtract calculation away.
- For milestone anniversaries counted from a start date (100 days together, 1,000 days), remember that some traditions count the first day as day 1 — that's inclusive counting, one day earlier than the plain gap.
Month and year conversions are average-based approximations. All calculations run entirely in your browser; the dates you enter are never sent anywhere or stored.
How many days until Christmas, New Year and more?
These are some of the most-counted-down dates on the calendar. The event names and dates below are fixed; the "days left" column updates automatically every time the page loads, so it's always current. Click any date into the Countdown tab above to see the full breakdown in weeks and months.
| Event | Date | Days left |
|---|---|---|
| Halloween | October 31, 2026 (Saturday) | — |
| Thanksgiving 2026 | November 26, 2026 (fourth Thursday of November) | — |
| Christmas Day | December 25, 2026 (Friday) | — |
| New Year's Day 2027 | January 1, 2027 (Friday) | — |
| Valentine's Day | February 14, 2027 (Sunday) | — |
| Independence Day | July 4, 2027 (Sunday) | — |
Counting down to a birthday instead? The Age Calculator tells you exactly how old you'll be — in years, months, and days — when the big day arrives.
Frequently asked questions
Does the countdown include today?
No. The countdown shows the number of midnights between today and the target date, so "3 days left" means the event is three days from now and today is not counted. On the day of the event itself the result reads "Today is the day".
When should I count the start date (inclusive counting)?
Use exclusive counting for gaps and intervals — hotel nights, days until a deadline. Use inclusive counting when the first day itself counts as a full day, such as rental periods, medication courses, or billable workdays. Inclusive counting always gives one day more than exclusive counting.
How accurate are the month and year conversions?
They are approximations. The calculator divides the day count by 30.44 (the average month, 365.25 ÷ 12) and by 365.25 (the average year including leap years). Because calendar months vary from 28 to 31 days, treat these figures as estimates only.
Does the time of day affect the result?
No. Every date is normalized to midnight (00:00) before comparing, so only the calendar dates matter. Whether you run the calculation in the morning or at night, the answer is the same.
Can I subtract days instead of adding them?
Yes. In the Add/Subtract Days mode, enter a negative number to go back in time. For example, entering -30 shows the date and weekday exactly 30 days before your base date.