Everyday
Date Calculator
Add or subtract days from a date. Change the inputs below and the estimate updates immediately.
Input
Your numbers
Calculated result
Resulting date
January 31, 2026
Estimate only. Verify important decisions with an appropriate professional or official source.
How to use it
A quick estimate, without the spreadsheet.
Inputs and units
Select a starting date and enter a whole number of calendar days, negative to subtract.
Formula
The date is advanced or reduced by the entered number of calendar days.
Worked example
January 1, 2026 plus 30 days is January 31, 2026.
Assumptions and limitations
Calendar days include weekends and holidays. The start date is day zero. This is not a business-day or legal-deadline calculator.
Keep calculating
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