Date Calculator — Add or Subtract Days
Use this date calculator to add or subtract days, weeks, months, and years from any date. Find any future date or past date instantly with our date plus days calculator.
Date Calculator — Add or Subtract Days
Add or subtract years, months, weeks, and days from any date
What Is a Date Calculator?
A date calculator lets you add or subtract a duration — any combination of years, months, weeks, and days — from a starting date to find the resulting date. Instead of flipping through a calendar counting squares, you enter your numbers and get the exact answer in seconds.
This date plus days calculator is perfect for finding project deadlines, contract expiry dates, warranty end dates, subscription renewal dates, and any other date that is a fixed number of days or months away from a known starting point.
How to Use the Date Calculator
- 1Select your start date using the date picker.
- 2Click the +/− toggle to choose whether to add or subtract.
- 3Enter the number of years, months, weeks, and/or days.
- 4Click "Calculate Date" to see the result date.
- 5The result shows the full date, day of week, day of year, and week number.
- 6Use the Quick presets for common amounts like "+30 days", "+6 months", or "+1 year."
Date Calculator Examples
Frequently Asked Questions
How do I add days to a date?
Enter your start date, make sure the +/− toggle is set to "+", enter the number of days (and optionally months, weeks, or years) to add, then click "Calculate Date." The result shows the exact future date.
How do I subtract days from a date?
Enter your start date, click the +/− toggle to switch to "−", enter the number of days or other units to subtract, and click "Calculate Date." The result shows the past date.
What is a future date calculator?
A future date calculator takes a starting date and adds a specific duration (days, weeks, months, or years) to find what date that will be. Use it to find deadlines, renewal dates, expiry dates, or any future event date.
Can I add months or years to a date?
Yes. The calculator supports adding or subtracting years, months, weeks, and days — all at once or individually. Month and year additions account for variable month lengths automatically.
What happens when adding months to dates like January 31?
When you add one month to January 31, the result is February 28 (or 29 in a leap year) because February doesn't have 31 days. The calculator uses JavaScript's native Date object, which handles these edge cases correctly.