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Add days

Add/subtract calendar days and expose timezone/calendar assumptions..

Your result

How to use Add days

  1. Enter the values you want to calculate and choose the relevant units or settings.
  2. The result updates as you type. Adjust the available settings if needed.
  3. Review the result, then use Copy result or a download link when available.

Useful next steps

Working with add days

Date calculations can depend on calendar rules, time zones and whether endpoints are included. A duration in hours is different from a number of calendar days when daylight-saving changes occur.

Common questions

Are all days exactly 24 hours long?

Elapsed time across a daylight-saving transition can differ from a simple calendar-day count. Use the measure relevant to your schedule.

Why can the same timestamp show different dates?

A timestamp represents an instant, while a calendar date is interpreted in a time zone. Near midnight, the same instant can fall on different local dates.

Continue your workflow: Date difference, Business days, Time zone converter.