Date Calculator
Days Between
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Result Date
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What is a Date Calculator?
A date calculator does two things: it counts the number of days between two dates, or it adds and subtracts days from a starting date to find a future or past date. Useful for deadlines, project timelines, contract terms, or any situation where you need to count calendar days precisely.
How It Works
Example
A lease starts on February 1 and runs for 90 days. When does it end?
- Feb 1 + 90 days = May 2
How long between March 10 and July 4?
- 116 days
Tips
- This calculator counts calendar days, not business days. Weekends and holidays are included in the total.
- For legal deadlines, clarify whether the start date or end date is counted. "30 days from today" sometimes means 30 full days starting tomorrow.
- Leap years are handled automatically. February has 29 days in leap years and 28 in all others.
Frequently Asked Questions
What is the difference between calendar days and business days?
Calendar days count every day including weekends and public holidays. Business days count only weekdays (Monday through Friday), excluding holidays. This calculator uses calendar days. Many legal and financial deadlines specify which type applies.
How do I calculate 30 days from today?
Use the "Add or Subtract Days" mode, set today as your start date, and enter 30 as the number of days to add. The calculator returns the exact date 30 calendar days from now.
Does this calculator account for leap years?
Yes. Leap years are handled automatically. If your date range includes February 29, it is counted correctly without any extra input from you.
How are date calculations used in legal and financial contexts?
Contracts often specify payment terms like "net 30" (payment due 30 days from invoice date), notice periods, warranty durations, and statute of limitations. Precise date calculation avoids disputes over when a deadline actually falls.