Calculate dates in seconds.
Need to calculate days between two dates, run a countdown, see days passed, or do date math? Use The Day date calculator.
Popular date calculations
These are the most common ways people calculate dates. The calculator page includes all of them in one place.
Days between two dates
Pick a start date and an end date to calculate the total days and a simple breakdown.
Countdown to a date
Calculate how many days are left until a target date (or how many days since).
Date + / − days
Add or subtract a number of days from a base date and get the resulting date and weekday.
Workday calculator
Calculate workdays vs weekends for a time period (and more tools on the calculator page).