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Date Calculator
Two everyday date problems in one tool: what date is N days from a start date (deadlines, due dates, travel planning), and how many days lie between two dates. All calendar math is done properly — leap years included.
Add or subtract days
Pick a start date and a number of days (negative numbers go backwards). The result accounts for month lengths and leap years automatically — 90 days from 1 January is 1 April in a normal year, 31 March in a leap year.
Days between dates
Enter both dates and get the exact day count, plus the same span in weeks and approximate months. Note the convention: the count excludes the start date and includes the end date (so 1 Jan → 2 Jan is 1 day), which matches how deadlines and bookings count.
Frequently Asked Questions
What date will it be in 30 days?
Enter today as the start date and 30 as the days — the tool does the month and leap-year math for you.
How are days between dates counted?
Start date excluded, end date included — the standard convention for deadlines, rentals and bookings.
Does it handle leap years?
Yes — the calculation uses real calendar dates, so 29 February is counted correctly in leap years.
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