Days between dates calculator

What is the days between dates concept?

The days between dates calculator is a handy tool that allows users to quickly and accurately calculate the number of days between two specific dates. This can be extremely useful in various scenarios such as event planning, calculating age, determining deadlines, and overall project management.

Essentially, calculating the number of days between two dates involves counting all those days that have passed from a given period start date to a given period end date. In this case, the end date is not included in the calculation. This method allows you to clearly understand how many full days have passed between two given points in time.

Formula

The basic formula employed to compute the number of days between two dates is as follows:

$\text{Days Between} = \text{End Date} - \text{Start Date}$

Where:

• The “End Date” is the final date up to which you are counting.
• The “Start Date” is the initial date from which you’re starting your count.

To execute such a calculation manually, one might convert the dates into Julian days or use a calendar system to encode this difference methodically.

Examples

Example 1: Calculating days between dates

Suppose you want to find how many days are between January 10, 2025, and February 10, 2025.

In this case, the number of days between January 10, 2025 and February 10, 2025 is 31 days.

Example 2: How many days are between December 15, 2025 and March 15, 2026?

For this calculation:

• December 15 to December 31 gives you 16 days.
• January covers all 31 days, February has 28 days (2026 isn’t a leap year), and until March 15 gives you 15 days.

So, summing these amounts results in 90 days total.

Example 3: Leap year consideration

Consider calculating between February 1, 2028, and March 3, 2028.

February 2028 is a leap year, offering up 29 days, and 3 days of March contribute 3 more days, making it 32 days in total.

Related topics

Our website provides many useful calculations regarding time and date. If you need to convert weeks to years or calculate the number of hours, you can use one of the following useful tools:

• Hours calculator;
• Weeks to years calculator;
• Days in year calculator;
• Age calculator;
• Time unit converter.

Frequently asked questions (FAQs)

How does the calculator account for leap years?

The calculator inherently includes leap year calculations, which adds an extra day for February every fourth year.

How many days are between December 5, 2025, and January 2, 2026?

Since December has 31 days, taking this into account, there will be 28 days between the indicated dates.

Why isn’t the end date included in the calculation?

The conventional approach to days-between-dates calculations excludes the end date to focus solely on full 24-hour periods between the dates. That is, for example, from 12:00 on December 5, 2025 to 12:00 on January 2, 2026 there will be 28 days.

Can the calculator handle historical dates?

Yes, the calculator can address any two valid dates as long as they fall within a calendar format it’s designed to interpret, including past years.

Does this calculator take into account weekdays and weekends?

This calculator does not separate weekdays and weekends, it calculates the total number of days between given dates.