How to Use This Date Calculator
Use the Add / Subtract Days tab to find a date a certain number of days before or after a starting date. Use the Days Between Dates tab to count how many days, weeks, months, or years separate two dates.
Common Uses
Date arithmetic comes up constantly: project deadlines, billing cycles, subscription renewals, legal notice periods, and more. This calculator handles leap years automatically so you never have to count on your fingers.
Adding and Subtracting Days
Enter any starting date, choose whether to add or subtract, then type the number of days. The result shows the full weekday and calendar date, plus how far in the past or future it falls relative to today.
Days Between Two Dates
Enter a start and end date to see the exact number of calendar days between them. The calculator also breaks the span down into complete weeks, months, and years for quick reference.