Add or Subtract Days Calculator
Find future or past target dates by adding or subtracting days, weeks, or months.
➕ Utility
Add / Subtract Days Calculator
Quickly add or subtract business days, calendar days, weeks, or months from any starting date.
Related Articles & Guidelines
Project deadlines and milestone dates by moving forward or backward in calendar days, business days, weeks, months, or years.
How to use Add / Subtract Days Calculator
- Enter the starting date directly or select it from the calendar picker.
- Choose add or subtract, enter the quantity, and select the appropriate unit.
- Compute the target date and verify its weekday before using it in a schedule.
Best practices & guidelines
- Use business days when weekends should not count.
- Check local holidays and organization-specific closure days manually.
- For month calculations, review dates near the 29th, 30th, or 31st.
- Record the starting date and rule used so others can reproduce the result.
QUICK ANSWERS
Frequently asked questions
Does business-day mode include Saturday?
No. It counts Monday through Friday and skips Saturday and Sunday.
What happens when adding one month to a month-end date?
The browser adjusts to a valid date when the target month has fewer days, so review month-end results carefully.
Privacy note: This tool processes inputs in your browser. Review sensitive information before copying, exporting, or sharing any result.