Days Calculator
Count calendar days, business days, and weekends between any two dates with custom end-date inclusion.
Breakdown: 2 months, 30 days
65
Mon - Fri26
Sat - SunDid this calculation save you time?
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What Is a Days Calculator?
A days calculator counts the exact number of days between two dates on the Gregorian calendar. It decomposes the total duration into working days (Monday–Friday) and weekend days (Saturday–Sunday), essential for court deadlines, leasing agreements, and project sprints.
How to Use This Calculator
- Select the start date.
- Select the end date.
- Check the box if you wish to include the end date in the count (+1 day).
- Review total calendar days, business days, and weekend counts.
Days Count Expression
D_{\text{total}} = \left\lfloor \frac{\text{Date}_2 - \text{Date}_1}{86,400,000} \right\rfloor + (\text{if inclusive: } 1)Calendar day count derived from 86,400,000 milliseconds per standard calendar day.
Worked Example
Scenario: Counting days from September 1 to November 30.
September has 30 days, October has 31 days, November has 30 days.
From Sept 1 to Nov 30 is 90 calendar days.
Includes 65 business days and 25 weekend days.
Tips & Key Notes
- Leasing and statutory notices often define deadlines in "calendar days" whereas banking and court filings use "business days".
- Quick presets (+30, +60, +90, +180, +365) allow 1-click timeline forecasting.
- Check state and federal holidays when calculating strictly operational business turnaround times.
Frequently Asked Questions
Does the calculator include both start and end days?
By standard convention, the start day is included and end day is excluded (delta duration). You can check "Include End Date" to count both days.
How many days are in a leap year?
A standard year has 365 days, while a leap year has 366 days due to the addition of February 29.
What are business days?
Business days are standard working days from Monday through Friday, excluding Saturdays and Sundays.
How many weeks are in 90 days?
90 days equals 12 full weeks and 6 days (or approximately 12.86 weeks).
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