Date Calculator — Days Between Dates & Add Days

Count the days between two dates, or add and subtract days, weeks, months, and years from a date. 100% in your browser — free, no sign-up.

How to

  1. 1Pick a mode: days between dates, or add/subtract from a date.
  2. 2Enter the date(s) — and any days, weeks, months, or years to add.
  3. 3Read the result instantly, including the day of the week.

What the date calculator does

Two things: it counts the exact number of days between two calendar dates — also broken down into weeks, approximate months, weekdays (Mon–Fri), and weekend days — and it adds or subtracts days, weeks, months, or years from a date, telling you what day of the week the result lands on.

How it works

Between two dates, the difference is the count of calendar days from the first date up to (and optionally including) the second — tick the checkbox if your counting should include the end date, as deadlines often do. Adding calendar units follows normal calendar rules: adding one month to January 31 rolls into early March, because February is shorter.

Weekdays vs business days

The weekday count includes every Monday to Friday in the span. Real business-day counts can differ because public holidays vary by country and year — treat the weekday number as the upper bound and subtract any holidays that apply to you.

When to use it

Deadline math (30 days from today), project timelines, counting down to an event, notice periods, visa and passport windows, invoice due dates, or figuring out what date it will be six weeks from now.

FAQ

How do I count days between two dates?+

Enter the From and To dates and the total days shows instantly, with weeks, approximate months, and a weekday count. Tick "Include end date" if the last day should count too.

What date is 30 days from today?+

Switch to Add / subtract, set today as the start date, add 30 days, and the result shows the exact date and its day of the week.

Does the weekday count skip holidays?+

No — it counts every Monday to Friday in the span. Public holidays vary by country and year, so subtract the ones that apply to you.

Why does adding a month sometimes shift the day?+

Calendar months have different lengths: one month after January 31 rolls into early March because February is shorter. That follows standard calendar rules.

Is it free?+

Yes, completely free — no sign-up and no watermark.

Is my data private?+

Yes — this tool runs entirely in your browser. Your files and text are never uploaded.

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