Date Calculator for Everyday Planning
Use this date calculator to count days between two dates, add days to a date, or move forward and backward by weeks, months, and years. It works well for deadlines, shipping estimates, notice periods, travel planning, and any situation where a manual calendar count is too easy to get wrong.
Examples
Common date calculations and their results:
| Start Date | Operation | Result (Calendar) | Result (Business) |
|---|---|---|---|
| Friday | +1 Day | Saturday | Monday |
| Friday | +3 Days | Monday | Wednesday |
| Jan 1 | to Jan 31 | 30 Days | 20-22 Days (varies) |
Calendar vs. Business Days
Calendar days count every day on the calendar, including weekends. Business days count only weekdays in this calculator. That distinction matters for project deadlines, shipping windows, payroll schedules, and office-based timelines.
Inclusive vs. Exclusive
By default, the calculator shows elapsed time between dates. If you need an inclusive count, add one day to the result so the start date is counted as part of the range.
Frequently Asked Questions
Q:How do I calculate the number of days between two dates?
Choose the start date and end date in 'Days Between Dates' mode. The calculator will return the elapsed number of days and weeks between them. Turn on the business-day option if you want weekends excluded.
Q:Does this date calculator account for leap years?
Yes, absolutely. Our algorithm follows the Gregorian calendar rules strictly, so February 29th is correctly counted in any range crossing a leap year (like 2028).
Q:Can I add months or weeks to a specific date?
Yes. Switch to 'Add / Subtract' mode, choose the unit you want to use, and then enter the quantity. You can add or subtract days, weeks, months, or years from any valid starting date.
Q:What are 'Business Days' in this calculator?
Business days in this calculator mean Monday through Friday only. Weekends are skipped, which makes the result more useful for office schedules, work estimates, and similar planning tasks.
Q:How do I verify a 90-day deadline?
Enter the start date in 'Add / Subtract' mode, set the operator to add, enter 90, and choose days as the unit. The result is the deadline date 90 days later.
Q:How do I add days to a date?
Switch to add/subtract mode, enter the starting date, choose add, and then enter the number of days, weeks, months, or years you want to move forward. The calculator updates the result automatically.