Date Calculator - Add, Subtract Days and Calculate Date Differences
Free date calculator to add or subtract days, weeks, months, and years from any date. Calculate the difference between two dates with precise results including leap year handling.
Date Calculator
Starting Date
Time to Add/Subtract
Date Calculation Methods
Date Calculation Examples
| Operation | Start Date | Time Period | Result | Use Case |
|---|---|---|---|---|
| Add | Jan 1, 2024 | 90 days | Mar 31, 2024 | Project deadline |
| Add | Mar 15, 2024 | 6 months | Sep 15, 2024 | Contract expiry |
| Subtract | Dec 25, 2024 | 30 days | Nov 25, 2024 | Preparation start |
| Subtract | Jul 4, 2024 | 2 weeks | Jun 20, 2024 | Planning phase |
| Difference | Jan 1, 2024 | Dec 31, 2024 | 365 days | Year duration |
| Difference | Mar 1, 2024 | May 15, 2024 | 75 days | Project length |
| Add | Feb 29, 2024 | 1 year | Feb 28, 2025 | Leap year handling |
| Difference | Birth date | Today | Age in days | Age calculation |
About Date Calculator
Our date calculator performs precise date arithmetic with automatic leap year handling and month-end adjustments. It can add or subtract years, months, weeks, and days from any date, or calculate the exact difference between two dates.
Date Calculation Features
The calculator handles complex date scenarios including leap years, varying month lengths, and month-end dates. When adding months to a date like January 31st, it intelligently adjusts to the last day of the target month if needed.
Common Applications
Use this calculator for project planning, contract dates, age calculations, deadline setting, event planning, loan calculations, and any situation requiring precise date arithmetic with professional accuracy.
Frequently Asked Questions
How do you add days to a date?
To add days to a date, simply count forward from the starting date. The calculator automatically handles month and year boundaries, including leap years. For example: January 25 + 10 days = February 4.
How does the calculator handle leap years?
The calculator automatically accounts for leap years when performing date calculations. It recognizes that February has 29 days in leap years (every 4 years, except century years not divisible by 400) and adjusts calculations accordingly.
What happens when adding months to month-end dates?
When adding months to dates like January 31st, the calculator intelligently adjusts to the last day of the target month if the exact day doesn't exist. For example: January 31 + 1 month = February 28 (or 29 in leap years).