Add or subtract days from dates and find date differences
Built & maintained by Pappu Venkata Subbi Reddy, founder of Clacify
Date Calculator finds the duration between two dates and adds or subtracts time from a date. Enter two dates to get the exact gap in days, weeks, months, and years; or enter a start date and add/subtract a number of days, weeks, or months to find the resulting date. It correctly handles leap years and varying month lengths. Useful for counting down to events, calculating deadlines and notice periods, working out durations for forms, or planning schedules. All calculation happens locally in your browser.
The difference between two dates is computed by converting both to a day count and subtracting, then expressing the result in years, months, and days by borrowing across months (using each month's real length) and leap years. Adding or subtracting time advances the date component-by-component, rolling over months and years correctly. All date maths runs locally in your browser.
Enter the start date and end date in Clacify's Date Calculator to instantly see the number of days, weeks, and months between them. For example, from 1 January 2025 to 26 May 2026 is 510 days.
Enter your start date in the Date Calculator and select '+ 30 days' to find the resulting date. Adding 30 days to 1 April 2025 gives 1 May 2025. Useful for calculating EMI due dates, return windows, license renewal dates, or notice period end dates.