Date Calculator
Add or subtract days, weeks, months, or years from any date, find out what date is X days from today, or count the days between two dates. Handles month lengths and leap years automatically.
Reviewed & updated for 2026 · How we calculate
How to use the date calculator
This tool has two modes. Use Add / subtract when you know a starting date and want to move forward or backward by a number of days, weeks, months, or years, for example, "what is the date 90 days from today?" or "what date is 6 weeks before my due date?". The result shows the exact calendar date and the day of the week.
Use Days between when you have two dates and want to know the gap, for example, "how many days until Christmas?" or "how many days ago was a deadline?". It returns the total number of days plus a breakdown in years, months, and weeks.
Days from today, at a glance
Common "days from today" results, calculated live from today's date:
| From today | Date |
|---|---|
| Loading… | |
Counts every calendar day, including weekends and holidays.
How date math works
Counting days between two dates is simple subtraction: take the later date minus the earlier date and divide the elapsed time by one day. The tricky parts are month lengths (28 to 31 days) and leap years (an extra day every four years, except century years not divisible by 400). This calculator handles both, so adding "one month" to January 31 correctly lands on the end of February rather than an invalid date.
When you add years and months first and then weeks and days, you avoid drift. For example, 90 days from a date is not exactly "3 months" because months vary in length, 90 days is sometimes 2 months and 28 days, sometimes 3 months exactly. That's why the day-count and the calendar date can differ slightly from a rough mental estimate.
For elapsed-time questions like age or project duration, the breakdown into years, months, and weeks is usually more useful than a raw day count. For deadlines and countdowns, the total day count is what matters.
FAQs
What date is 90 days from today?
To find the date 90 days from today, add 90 days to today's date, roughly 3 months ahead. Enter 90 in the Days field of the calculator above and it shows the exact date and day of the week, accounting for different month lengths and leap years.
How do I calculate the number of days between two dates?
Subtract the earlier date from the later one. The 'Days between' tab above does it instantly and also breaks the gap into years, months, and weeks. For example, January 1 to December 31, 2026 is 364 days.
How many days until a future date?
Use the 'Days between' tab with today as the start date and your target as the end date. It counts every calendar day until that date, so you can see how many days are left until a deadline, holiday, or event.
How do I add or subtract days from a date?
Pick a start date, choose Add or Subtract, then enter any combination of years, months, weeks, and days. The calculator handles month lengths and leap years for you, so 'one month after January 31' lands correctly.
How many days ago was a past date?
Switch to the 'Days between' tab, set the past date as the start and today as the end. The result is the number of days that have passed. You can also use Add/Subtract mode with the Subtract option to count backward from today.
Does the date calculator count weekends and holidays?
Yes. It counts every calendar day, including weekends and public holidays. If you need business days only (Monday to Friday), subtract the weekend days separately, as this tool measures total elapsed calendar days.