Date Calculator
Calculate exact days between two dates, or add/subtract days, weeks, and months from any date.
Date Interval
Days Between Dates
30 days
4 weeks, 2 days
Business days
22 days
Weekend days
8 days
How it works
The Date Calculator provides two primary tools: calculating the duration between two calendar dates, and adding or subtracting days from a date.
Days Between Dates computes the exact calendar duration, broken down into years, months, days, total weeks, and business days (Monday through Friday).
Add / Subtract Days allows you to project forward or backward in time by days, weeks, months, or years, with an option to skip weekends.
Great for project planning, vacation counting, lease deadlines, and legal notice timelines.
Frequently asked questions
- How are business days counted?
- Business days include Monday through Friday and exclude Saturdays and Sundays. Official public holidays are not excluded because they vary by country and jurisdiction.
- Should I check 'Include end date'?
- Check 'Include end date' if you want both the start day and the end day counted in full (inclusive counting).
- How does adding a month to January 31 work?
- If a target month has fewer days than the start date, the date rolls over to the end of that month (for example, January 31 + 1 month adjusts to the end of February).
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