How the date calculator works
Pick a start date, type a number, and choose whether to add or subtract it. The calculator instantly returns the resulting date and tells you which weekday it lands on. Use it to answer questions like "what date is 90 days from today?" or "what was the date 45 days ago?" without counting on a calendar.
Calendar days vs. business days
By default the calculator counts every calendar day, including weekends. Switch on the business-days-only option to skip Saturdays and Sundays — and, if you pick a country, its public holidays too. This is ideal for delivery windows, payment terms and contractual deadlines that run in working days.
Common uses
- Finding a deadline a set number of days from today
- Calculating invoice due dates and net payment terms
- Working out shipping and delivery dates
- Counting back from an event to plan preparations
Frequently asked questions
What date is 90 days from today?
Set the start date to today, type 90, keep the unit on Days and choose Add. The result updates instantly with the exact date and weekday.
How are months and years handled?
Adding months or years keeps the same day number when possible. If the target month is shorter (for example adding one month to January 31), the result is clamped to the last day of that month.
Does it work offline?
Calendar-day calculations run entirely in your browser. The only time an internet connection is needed is when business-days-only mode fetches the public holiday list for your selected country.