Month Calculator
Count the Months Between Dates
Use the month counter below to find the number of full months between any two dates.
Result: Months Between Dates
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Joe is the creator of Inch Calculator and has over 20 years of experience in engineering and construction. He holds several degrees and certifications.
How to Calculate the Number of Months Between Two Dates
You can count the number of months between dates by following a few easy steps. Before you begin, you’ll need the start date and the end date.
Step One: Count the Full Months
To calculate the number of full months between a start date and an end date, you’ll need to find the year and month difference.
You can use a formula to find the difference in months:
month difference = {(end year – start year) × 12} + (end month – start month)
The result is the total difference in months, ignoring the specific days.
Then, you need to adjust for partial months.
If the end day is less than the start day, then the last month isn’t complete. You must subtract 1 month from the total difference in months.
For example, let’s calculate the difference in months between March 20, 2026 and July 15, 2026.
month difference = {(2026 – 2026) × 12} + (7 – 3)
month difference = {0 × 12} + 4
month difference = 4
At this point, we need to account for partial months to find the number of full months between these dates. Since the day portion of the end date is less than the day portion of the start date (15 < 20), we need to subtract 1 month from the difference.
full months = 4 – 1 = 3
So, the number of complete months between March 20, 2026 and July 15, 2026 is 3.
Step Two: Calculate the Remaining Days
Once you know the number of whole months between dates, you can calculate the remaining days by adding the number of full months to the start date, then finding the number of days between these dates.
For example, let’s see how to do this using the dates in our example above: March 20, 2026 and July 15, 2026.
Start by adding the difference in months from the first step to the start date.
adjusted date = March 20, 2026 + 3 months = June 20, 2026
Next, count the number of days between June 20 and July 15 – the result is 25 days. You can use our days between dates calculator to confirm.
Therefore, the total amount of time between March 20, 2026 and July 15, 2026 is 3 months and 25 days.
Frequently Asked Questions
Does a Leap Year Affect the Calculation?
While there is an additional day in February during a leap year, this does not change the steps used to count months between dates shown above.
Here’s why:
When counting months, each month is treated as a discrete unit (January, February, etc.), regardless of how many days it contains. Leap years only affect day counts, not month boundaries.
However, leap years can affect the remaining days portion if your time span crosses February in a leap year.
For example, from January 28, 2024 to March 2, 2024:
full month count = 1 (February 28 → March 2)
remaining days = 3 (29, 1, 2 — because February had 29 days in 2024).
So while the month count stays the same, the day count may increase by one in leap years.
For the most accurate results, use our day counter to calculate.
How Many Days Are In a Month?
There are 28-31 days in a month, depending on the month. Check out the chart showing the number of days in each month of the year on our months to days converter.
How Do You Find the Date a Certain Number of Months From Today
What if you need to project forward to find the date in a certain number of months–for instance, what date is 6 months from now?
You can calculate the date N months from a given date in a few easy steps:
- Add N months to the month value of your date.
- Adjust for year overflow: if the month number exceeds 12, divide by 12 to carry over full years.
- Adjust the day: if the target month has fewer days than the original date (for example, adding 1 month to January 31), use the last valid day of that month (February 28 or 29 in a leap year).
You can also use our months from today calculator to find the date.