Date Time Calculator
Instantly add or subtract time from any date. Enter a start date and time, specify the years, months, weeks, days, hours, minutes, or seconds to change, and see the exact result formatted for your locale.
Date Time Calculator
Quick Date-Time Calculations
How to use this date time calculator
- Select a Start date and Start time, or click Use now to select the current time.
- Choose to Add or Subtract time.
- Enter the duration values—Years, Months, Weeks, Days, Hours, Minutes, and Seconds.
- Click Calculate to view the resulting Date, Time, and Weekday.
Notes
- Years and Months are added as calendar adjustments, accounting for leap years and varying month lengths.
- Weeks and Days are calculated as fixed durations.
- The output format matches your browser's locale or the selected language.
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