Date Adder Calculator
Pick a starting date, choose add or subtract, and enter days, weeks, months and years — the result date handles month ends and leap years correctly.
Pick a date to see the result.
How to use
- Pick the start date (today is prefilled).
- Choose Add or Subtract and enter any mix of years, months, weeks and days.
- Read the resulting date with its day of the week.
Months and years are added on the calendar first, with the day clamped to the last day of the target month (for example 31 January plus 1 month becomes 28 or 29 February), then weeks and days are added. All math uses the local calendar with no time zone shifting.