Days between two dates
Pick a start date and an end date to see how many days are between them, also expressed in weeks and days and in approximate months. It answers questions like how many days are left until a trip, a wedding or a due date, how long ago something happened, or how many days a rental, a loan or a hospital stay lasted.
Turn on "Count the last day too" when both days should count, as with a hotel booking, a vacation or a course that runs from one date to another inclusive.
Add or subtract days
Start from a date and add or subtract a number of days to get the resulting date. That is how you find the date that is 30, 60 or 90 days after an invoice, when a return window or a warranty ends, when a medical treatment finishes or what date was 100 days ago.
The result counts calendar days, weekends included. For deadlines that only count working days, use the business days mode.
Business days and holidays
The business days mode counts the days from Monday to Friday between two dates and, if you want, also skips the national holidays of 2026 and 2027 for the United States, Mexico, Colombia, Argentina, Chile, Peru, Venezuela, Spain or Brazil. It shows how many holidays were excluded. State, regional and local holidays are not included, so subtract them yourself if they apply to you.
It is useful for delivery times, payment terms, notice periods and deadlines that are counted in business days. If a contract or an office sets its own rules for counting, follow those rules. There is a Business days calculator page that starts in this mode.
Exact age
Enter a date of birth and get the exact age in years, months and days, as of today or as of any date you choose. That helps with forms that ask for age on a specific date, with a baby's age in months, with the age a person will have on a trip or an exam day, or with the age of a pet, a building or a company. The Age calculator page starts here. Everything is calculated in your browser, free and without sign-up.