Free Date Calculator - How Many Days Between Two Dates?

Calculate the number of days, weeks, months, and years between any two dates. Find out how many days until an event or how many days since a past date — instantly.

How to Use This Date Calculator

This calculator has three modes. Days Between Dates calculates the exact number of days, weeks, months, and years between any two dates — with an option to count only business days. Days Until Event counts down to any future date or calculates how many days have passed since a past date. Add or Subtract Days finds a new date by adding or subtracting any number of days, weeks, months, or years from a starting date.

How to Calculate the Number of Days Between Two Dates

To calculate days between two dates, subtract the earlier date from the later date. The result gives you the total number of calendar days. This sounds simple but the calculation needs to account for leap years — years divisible by 4 that have 366 days instead of 365 — which adds complexity when calculating over long periods.

For example, the number of days between January 1, 2020, and January 1, 2026, is not simply 6 times 365. Because 2020 and 2024 were both leap years the actual count is 2,192 days.

Business Days vs Calendar Days

Calendar days count every day including weekends and holidays. Business days count only Monday through Friday excluding weekends. Business day calculations are important for contract deadlines, loan processing times, shipping estimates, legal notices, and workplace project planning.

Most business and legal contexts use business days rather than calendar days. When a contract says payment is due in 30 days that typically means 30 calendar days. When it says 30 business days that excludes weekends and adds approximately 12 extra days to the deadline.

Common Uses for a Date Calculator

Project deadlines — calculate how many days or business days remain until a project is due so you can plan your work schedule accordingly.

Contract and legal deadlines — many legal documents specify deadlines in days from a triggering event. A date calculator helps ensure you never miss a deadline.

Loan and mortgage calculations — mortgage closing timelines, loan processing periods, and grace periods are all measured in days. Knowing exactly how many days remain helps you stay on track.

Pregnancy due dates — a pregnancy lasts approximately 280 days or 40 weeks from the first day of the last menstrual period. Date calculators are commonly used to estimate due dates and track pregnancy milestones.

Event planning — wedding planners, event coordinators, and individuals planning major life events use date calculators to count down and plan timelines.

Travel planning — knowing exactly how many days until a trip helps with booking, packing, and preparation schedules.

Age verification — businesses and government agencies often need to calculate whether someone has reached a specific age as of a certain date.

How to Add Days to a Date

To add days to a date simply count forward on the calendar from your starting date. For small numbers this is easy to do manually but for larger numbers like adding 90 days or 6 months a date calculator prevents errors.

Adding months is trickier than adding days because months have different lengths. Adding one month to January 31 results in February 28 or 29 in a leap year because February does not have 31 days. Our calculator handles this automatically.

Adding years is similarly straightforward except when dealing with February 29 in leap years — adding one year to February 29, 2024, results on February 28, 2025, since 2025 is not a leap year.

Days Until Common Events in 2026

People frequently search for how many days until major holidays and events. Here are some key dates in 2026 along with their day of the week:

Independence Day — July 4, 2026, falls on a Saturday.

Halloween — October 31, 2026, falls on a Saturday.

Thanksgiving — November 26, 2026, falls on a Thursday.

Christmas — December 25, 2026, falls on a Friday.

New Year's Day 2027 — January 1, 2027, falls on a Friday.

Use the Days Until Event tab above to get an exact countdown to any of these dates from today.

Frequently Asked Questions

How many days are in a year?

A standard year has 365 days. A leap year has 366 days. Leap years occur every four years in years divisible by 4 — such as 2024, 2028, and 2032. The exception is years divisible by 100 which are not leap years unless also divisible by 400.

How do I calculate how many weeks between two dates?

Divide the total number of days by 7. If there are 91 days between two dates that is exactly 13 weeks. If the result is not a whole number the remaining days are expressed as extra days beyond the last complete week.

What is the difference between a calendar day and a business day?

A calendar day includes all seven days of the week including Saturday and Sunday. A business day includes only Monday through Friday — the standard working days. Some industries also exclude federal holidays from their business day counts.

How many days are in each month?

January has 31 days. February has 28 days or 29 in a leap year. March has 31 days. April has 30 days. May has 31 days. June has 30 days. July has 31 days. August has 31 days. September has 30 days. October has 31 days. November has 30 days. December has 31 days.

How do I calculate 90 days from today?

Use the Add or Subtract Days tab above — enter today's date, select Add, choose Days, and enter 90. The calculator will show you the exact date that falls 90 days from today along with the day of the week.

Why do some months feel longer than others?

February is the shortest month with only 28 or 29 days. January, March, May, July, August, October, and December all have 31 days. April, June, September, and November each have 30 days. The difference between the longest and shortest months is 3 days which can make some months feel significantly longer or shorter.

Results are calculated based on the Gregorian calendar. All calculations account for leap years. Results are for informational purposes only.