Date Calculators
Free online date calculators for adding days, finding differences, counting business days, and calculating due dates.
How to calculate days between dates: Select one of the calculators below to add or subtract days from any date, find the exact number of days between two dates, count only business days (excluding weekends and holidays), or calculate a due date. All calculations are instant and work in your browser.
About date calculators
Our free date calculators help you work with dates quickly and accurately. Add or subtract days from any date, find the exact number of days between two dates, count only business days (excluding weekends), calculate the day of the week for any date, or estimate pregnancy due dates. All calculations happen instantly in your browser.
Frequently asked questions
How do I count business days between two dates?
Use our Business Days Calculator. Enter your start and end dates, and it will count only weekdays (Monday–Friday), excluding Saturdays and Sundays. It can also exclude US federal holidays.
Can I add or subtract days from a date?
Yes. The Add/Subtract Days calculator lets you enter any start date and add or subtract any number of days. It correctly handles month boundaries, leap years, and shows the resulting date with the day of the week.
Does the calculator account for leap years?
Yes. All our date calculators correctly handle leap years (years divisible by 4, except century years not divisible by 400). February 29 is properly included or excluded in all calculations.