Add / Subtract Days

Find a future or past calendar date.

How to use the Add / Subtract Days

Find a future or past calendar date. Fill in the fields above and the result updates instantly, together with the formula behind it.

Formula

Add or subtract a whole number of UTC calendar days

Worked example

45 days after November 6, 2026 is December 21, 2026.

Important things to know

Calendar days include weekends; holidays are not excluded.

Frequently asked questions

How is the Add / Subtract Days calculated?

Add or subtract a whole number of UTC calendar days. Example: 45 days after November 6, 2026 is December 21, 2026.

What do I need to enter in the Add / Subtract Days?

You enter: Number of days; Direction; Start date. An example value is shown in each empty field, and the result appears as soon as the numbers are valid.

Does adding days handle month lengths and leap years?

Yes. Days are counted as calendar days, so adding 45 days to 6 November 2026 correctly gives 21 December 2026, and 29 February is handled in leap years.

Can I save or share this calculation?

Yes. Use Copy to copy the result or full example. Share creates a link that puts your chosen values into the URL fragment so another person can reproduce the calculation. Your named saves and recent history stay in your own browser.

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