Add Days to a Date Calculator

Choose a start date and how many days to add. The start date begins as today.

Updated October 27, 2026

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Code to copy

<iframe src="/embed/en/time-date/add-days-to-date-calculator/" width="480" height="640" title="Add Days to a Date Calculator" loading="lazy" style="border:0;max-width:100%"></iframe>
<script>window.addEventListener('message',function(event){if(event.origin!==''||!event.data||event.data.type!=='calc-embed-height')return;var f=document.getElementsByTagName('iframe');for(var i=0;i<f.length;i++){if(f[i].contentWindow===event.source){f[i].style.height=event.data.height+'px';}}});</script>

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Formula

new date = start date + days

The count uses whole calendar days, so month lengths and leap years are handled automatically. Weekends and holidays are not skipped.

Worked example

31 January 2024 plus 30 days:

29 days after 31 Jan 2024 is 29 Feb 2024 (2024 is a leap year)
1 more day is 1 March 2024, a Friday

Frequently asked questions

How do I add days to a date?

Count forward one calendar day at a time, rolling into the next month when you pass the last day. 31 January 2024 plus 30 days is 1 March 2024.

Does it handle leap years?

Yes. 1 January 2024 plus 366 days is 1 January 2025, because 2024 has 366 days.

Does this skip weekends or holidays?

No. Every calendar day counts, including weekends. To count only Monday to Friday, use the business days calculator.

Is the start date counted as day 1?

No. Adding 1 day to 1 June gives 2 June, and adding 0 days gives the start date itself.

How we calculate

Add Days to a Date Calculator

Formula

Worked example

Frequently asked questions

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