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Get NordVPN →Date Calculator — Add or Subtract Days, Months & Workdays
Two modes: 'add or subtract' to compute a future or past date, or 'between' to find the difference in years, months, days, weeks, and business days.
Result date
Tuesday, October 6, 2026
Related tools
How it works
What it computes
Add/subtract mode: takes a date, adds or subtracts a number of years, months, and days, and gives you the resulting calendar date. Years and months use calendar arithmetic (so adding 1 month to Jan 31 gives Feb 28 or Feb 29 depending on leap year, not Mar 3). Days are exact — adding 30 days always advances exactly 30 calendar days.
Between mode: takes two dates and gives the difference in years/months/days plus totals in days, weeks, months, and business days (Monday through Friday; public holidays are excluded too when you pick a holiday preset). The Y/M/D form uses the same borrow logic as our age calculator — a difference is e.g. '2 years, 5 months, 3 days', not a decimal year.
Business days and public holidays
Business days are Monday through Friday; Saturday and Sunday are always skipped. You can also pick a public-holiday preset — United States (federal holidays), Japan (national holidays), United Kingdom (England & Wales bank holidays) or Germany (nationwide holidays) — and those holidays are skipped as well, both when adding or subtracting business days and in the business-day count between two dates. The skipped holidays are listed under the result. With no preset (the default), only weekends are skipped.
The holiday data covers 2026–2027 and is the same as in our Workdays Calculator, including substitute and observed days. Regional holidays (such as German state holidays or Scottish bank holidays), other countries and company closures are not included — for those, use the Workdays Calculator, where you can add your own dates, or adjust the result by hand.
Common use cases
Project deadlines: 'this is due 90 days after kickoff'. Add 90 days to the start date.
Contract terms: count days between contract start and end. Match against your contract language for billing.
Travel planning: how many business days between leaving and returning? Useful for out-of-office calendars and expense reports.
Personal milestones: anniversaries, sobriety counts, time since a major life event.
Frequently asked questions
›What happens if I add 1 month to Jan 31?
You get Feb 28 (or Feb 29 in a leap year). Calendar arithmetic clamps to the last day of the target month when the source day doesn't exist.
›What date is 205 business days from July 16, 2026?
Tick 'Business days only', choose Add, enter 205 days and the start date Thursday, July 16, 2026. With weekends skipped only, the result is Thursday, April 29, 2027. With the US preset, 8 federal holidays (Labor Day through Presidents' Day) are skipped as well and the result moves to Tuesday, May 11, 2027. The result always shows the day of the week.
›How do I work out '4 months less a day' from a date?
Add 4 months first (Thursday, November 5, 2026 → Friday, March 5, 2027), then subtract 1 day: Thursday, March 4, 2027. To count the workdays in that period, switch to 'Difference between dates' with November 5, 2026 and March 5, 2027 — the end date is not counted, so you get the workdays from Nov 5 through Mar 4: 86 with weekends skipped, 80 with the US holiday preset.
›How many days is 5 years minus 262 days?
It depends on how many leap days fall in the span. From January 1, 2026, five years later is January 1, 2031 — 1,826 days, because February 29, 2028 is included. Subtract 262 days and you land on Sunday, April 14, 2030, which is 1,564 days after the start. In this calculator: add 5 years to the start date, then subtract 262 days from that result; the 'Difference between dates' mode shows the total days.
›Are holidays subtracted from business days?
Only if you pick a holiday preset. By default only Saturdays and Sundays are skipped. With the US, Japan, UK or Germany preset, that country's 2026–2027 public holidays are skipped too. Example: 10 business days after Thursday, April 30, 2026 is May 14 with weekends only, but May 19 with the Japan preset (May 4–6 are holidays).
›Does it handle negative date arithmetic?
Yes via the 'subtract' mode. Internally, subtraction is just adding negative deltas. The 'difference between' mode always returns positive values regardless of order.
›What time zone does this use?
Your browser's local time zone. Dates are interpreted as midnight local. Cross-time-zone calculations may need adjustment.
›Can I add hours and minutes?
Not yet — date granularity only. Use a separate timestamp tool for hour-level math.
›What's the largest difference it handles?
Hundreds of years comfortably. JavaScript's Date supports ±100 million days from 1970, so this is the practical limit.
›Why does it count both endpoints differently?
Total days is the count of nights between the two dates. Two consecutive days have a difference of 1 day. Business day count walks through each calendar day in between.
›Does the data leave my browser?
No. All math runs locally.
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