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Calculators

Date Add and Subtract Calculator

Add or subtract days, weeks, months, or years from any date instantly

Date Calculation

Quick Presets

Result

Jul 25, 2026Saturday, July 25, 2026
Start DateThursday, June 25, 2026
Operation+30 days
Result DateSaturday, July 25, 2026
ISO Format (YYYY-MM-DD)2026-07-25
Calendar Days Apart30 days
Day of WeekSaturday
Week 30 of 2026Day 206 of 2026

How it works: Days and weeks shift the date by the exact number of calendar days. Months and years preserve the day of month where possible — for example, January 31 + 1 month becomes February 28 (or 29 in a leap year). All calculations use local time and no timezone conversion.

About

The Date Add and Subtract Calculator lets you quickly find a future or past date by adding or subtracting any number of days, weeks, months, or years from a starting date. Whether you are calculating a project deadline, contract expiry, subscription renewal, or payment due date, this free tool gives you the exact result date along with the day of week and ISO format.

FAQ
How do I add 30 days to today's date?+

Click the 'Today' button to set the start date, choose 'Add' as the operation, enter 30 in the amount field, and select 'Days' as the unit. The result date appears instantly below.

What happens when I add months to a date like January 31?+

The calculator clamps the result to the last valid day of the target month. For example, January 31 + 1 month becomes February 28 (or February 29 in a leap year), so you never get an invalid date.

Can I subtract dates to go backwards in time?+

Yes. Select 'Subtract' from the Operation dropdown and enter your amount and unit. For example, subtract 6 months from a date to find what date it was half a year ago.

Does the calculator account for time zones?+

All calculations use your local calendar date with no timezone conversion, so the result matches the date shown on your device's clock rather than a UTC offset.

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