Date Add / Subtract Calculator

The date add/subtract calculator lets you find what date falls a specific number of days, weeks, months, or years from any starting date. Need to know what date is 90 days from today? When is 6 months after your contract start date? What was the date 2 years ago? Just enter the date, choose add or subtract, and get your answer instantly with the day of the week included.

The calculator correctly handles all edge cases: leap years (February 29), month-end boundaries (adding 1 month from January 31 gives February 28 or 29), and year transitions. Weeks are converted to days (×7) for precise calculation. This makes it reliable for contract deadlines, visa expiration calculations, medical follow-up scheduling, and project timeline planning.

Common use cases include calculating notice periods (30, 60, or 90 days from a given date), determining warranty expiration dates, finding delivery dates for shipping estimates, and computing age-related milestones. Use this alongside our Days Between Dates calculator to find the gap between two known dates, and our Week Number Calculator to find which ISO week a date falls in.