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Add or Subtract Days from a Date

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

Amount

Add or subtract
Unit
Result
Pick a start date and an amount to see the result.

Calculated in your browser. Dates are handled as whole calendar days, so daylight saving never shifts the answer.

How to add or subtract days from a date

  1. Pick a start date

    The field starts on today, and you can change it to any date you want to count from.

  2. Choose add or subtract

    Set the direction, then type how many days, weeks, months, or years to move.

  3. Skip weekends if you need to

    Turn on business days only to count working days rather than calendar days.

  4. Copy the result

    Copy the resulting date in standard format for reuse.

Why use this tool

Four units, both directions

Move by days, weeks, months, or years, forwards or backwards, without switching to a different calculator.

Business days option

Counts working days and skips Saturdays and Sundays, which is how notice periods, delivery windows, and payment terms are usually written.

Month ends handled properly

Adding a month to 31 January lands on the last day of February rather than spilling into March, which is the behaviour contracts assume.

Daylight saving cannot skew it

Dates are treated as whole calendar days, so a span that crosses a clock change is never a day out.

Nothing leaves your browser

The calculation runs locally, so deadlines and dates you are working with are never uploaded.

About this tool

This is the calculator for questions shaped like "what date is 90 days from today" or "what was the date 6 weeks ago". You set a start date, choose whether to move forwards or backwards, and pick how far in days, weeks, months, or years. The answer appears immediately with the weekday spelled out, because the weekday is usually the thing that decides whether a deadline is workable.

Two details make the difference between a right and a wrong answer. Calendar months are not a fixed number of days, so adding a month to 31 January gives the last day of February rather than the 2nd or 3rd of March. And a business day count is not the same as a calendar count: turning on business days only steps over Saturdays and Sundays, which is how contractual notice periods, statutory deadlines, and shipping estimates are normally written. Note that public holidays vary by country and are not deducted here.

Everything is worked out as whole calendar days, so a span crossing a daylight saving change is never off by one. If you want the gap between two dates you already have rather than a date at a distance, use the date difference calculator. For a live countdown to something specific, days until date keeps ticking, and the business days calculator covers working day spans in more detail.

Frequently asked questions

What date is 90 days from today?
Leave the start date on today, choose add, type 90, and keep the unit on days. The result shows the date and the weekday it falls on.
Does the business days option skip public holidays?
No. It skips Saturdays and Sundays only. Public holidays differ by country and region, so subtract them yourself if your deadline depends on them.
What happens when I add a month to the 31st?
The result clamps to the last day of the target month, so 31 January plus one month is 28 or 29 February depending on the year.
Is my date information uploaded anywhere?
No. The calculation happens in your browser, so nothing about your deadlines is sent to a server.
Can I count backwards?
Yes. Choose subtract and the same units apply, so you can work out the date a fixed period before a deadline.

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