Date Calculator: Days Between Dates & Add Days
Updated · Free · No sign-up · Runs in your browser
Find how many days are between two dates, or which date falls a given number of days before or after a start date. Results include the day of the week and the span in weeks and months.
Plan deadlines, notice periods, trips, due dates and subscription renewals. Leap years are handled automatically.
Days added to Saturday, October 24, 2026
| Days added | Date |
|---|---|
| +7 days | Saturday, October 31, 2026 |
| +14 days | Saturday, November 7, 2026 |
| +30 days | Monday, November 23, 2026 |
| +45 days | Tuesday, December 8, 2026 |
| +60 days | Wednesday, December 23, 2026 |
| +90 days | Friday, January 22, 2027 |
| +100 days | Monday, February 1, 2027 |
| +180 days | Thursday, April 22, 2027 |
| +365 days | Sunday, October 24, 2027 |
Worked examples
Days between Jan 1 and Dec 25, 2026
- Dec 25 − Jan 1
→ 358 days (359 counting both ends)
90 days after Oct 24, 2026
- Oct 24 + 90 days
→ Friday, January 22, 2027
30 days before Mar 15, 2027
- Mar 15 − 30 days
→ Saturday, February 13, 2027
Feb 10 to Nov 3, 2026 in months
- 266 days
→ 8 months 24 days
How to count the days between two dates
- Choose "Days between dates".
- Pick the start date and the end date.
- The result is end − start. Add 1 if you count both the first and the last day (for example, hotel nights vs. days of a festival).
How to add or subtract days from a date
- Choose "Add / subtract days".
- Pick a start date and type the number of days.
- Choose Add or Subtract to see the resulting date and weekday.
All results are calendar days — weekends and public holidays are included. Months have different lengths, so "1 month" is counted to the same day number in the next month (Jan 31 + 1 month = Feb 28 or 29).
Frequently asked questions
How do I calculate the number of days between two dates?
Subtract the start date from the end date. The calculator does this for you and handles leap years and different month lengths.
Does the result include the end date?
The main result does not include the start day (Jan 1 to Jan 2 is 1 day). The "counting both ends" figure adds 1, which is what you want when counting days of an event.
How many days are in a year?
365 days, or 366 in a leap year. 2028 is the next leap year; a year is a leap year if it is divisible by 4, except centuries not divisible by 400.
What date is 90 days from today?
Choose "Add / subtract days", leave the start date as today and enter 90. The result date and its weekday appear instantly.
Does it count business days?
No. It counts calendar days, including weekends and holidays. Business-day counts depend on your country's public holidays.
Are my dates saved?
No. The calculation runs in your browser and nothing is stored or sent anywhere.