# DATEDIF How to Calculate Difference Between 2 Dates (Many Examples)

The `DATEDIF` function calculates the number of periods between two dates. The best way to remember this function is it calculates the DATE DIFference between two dates.

## What Is `DATEDIF`?

The `DATEDIF` formula calculates the difference between two dates according to a third parameter determining the type of difference needed, for example, days, months, years (etc).

The `DATEDIF` function is a popular formula that has 3 parameters that are all required. If you encounter any error when using this function check you have populated all three fields correctly.

The function reference is as follows:

``=DATEDIF(start_date, end_date, unit) ``

The `start_date` parameter should be the earliest date, the `end_date` being the latest date, and the `unit` is the value of the periods you want returned from the difference between those two dates.

Accepted values in Google Sheets for the `unit` value are:

### Date Difference In Days

By setting the third parameter to the `DATEDIF` formula to `D` it means the resulting value returned will calculate the number of days between the two dates. Here are some examples:

Several things to note about these tests when using the `DATEDIF` function and the `unit` parameter as `D`:

1. The dates are not inclusive. Notice the first row is 0, if it were inclusive it would have been 1.
2. Should the `end_date` come before the `start_date` you will get an `#NUM!` error. Make sure your `end_date` occurs on or after the `start_date`.

### Date Difference In Months

If you want to calculate the difference between two dates in months, then set the third parameter of the formula to `"M"`, here are some interesting examples of what this looks like for certain values:

As can be seen from the table above, the day of the month needs to be either eclipsed or matched for the returning value to increment. In rows 5 and 6 especially we can see the days in the month of February 2020 would not have eclipsed the `start_date` of 31st January 2020, but when the `end_date` advances into the next month (1st March) the increment occurs.

Therefore, if your `start_date` is the end of a month containing 31 days it will not be until the 1st day of the following month, preceding a month containing only 28, 29 or 30 days, that the value will be incremented.

### Date Difference In Years

If you want to calculate the difference between two dates as years then set the third parameter value to `"Y"`. Here is what this would look like based on the following inputs:

As can be seen from the examples above, it’s not until the date and month of the `start_date` has been eclipsed or matched the value returned by the `DATEDIF` formula increments. This is very similar to when calculating the date difference in months.

### Date Difference In Days Irrespective of Months

If you need to calculate the difference in days between two dates irrespective of the difference between months then you’ll need to use `"MD"` as the value of the third parameter, as demonstrated below:

As previously noted with the difference in days we can see from the examples above the difference in days is not inclusive. However, there are some interesting results:

Row 3 shows a result of `-1`.

Why?

This implies there was a day short in the previous month of getting to the same date, and the current date of 1st March 2020 is 1 day short of the 31 days (29 days in February + 1 day in March = 30 days – 31 days = -1). This then puts the remaining values of that month (in March) out, until we hit the new month April.

### Date Difference In Whole Months Irrespective Of Years

If you want to calculate the difference between two dates in whole months irrespective of the difference in years you can set the third parameter to the `DATEDIF` formula to `"YM"`.

As you can see from the first row in the spreadsheet result above even though the year of the second date in column B is 2022 the result is still `0` as the difference in dates is compared irrespective of the year.

The remaining results are consistent with what we already know about when calculating the difference in months.

### Date Difference In Days Irrespective of Years

Similar to our previous example with date differences in days irrespective of months we have a similar calculation but this time irrespective of years, here are some examples:

Consistent with the days’ difference irrespective of months we see that where the start date isn’t matched by day of month and month, it calculates the difference the previous month fell short.

## `DATEDIF` Quarters

How do you calculate the difference between two dates in quarters? Recently I had a need where I had to calculate the remaining payments on a lease that was being paid once every 3 months. There were a couple of methods of approaching it:

Here’s how both approaches worked for me:

As you can see from the above examples, the most precise calculation is using `DATEDIF` with the `unit` parameter set to `"M"` and dividing that result by `3` rather than the alternative method of using `"D"` and dividing by 90 or 91.25.

Therefore, when calculating the difference between two dates to find the number of quarters between two dates use the formula: `=DATEDIF(start_date, end_date, "M")/3`

If you only want to know the whole number of quarters that have occurred between the two dates then you could wrap the function in `TRUNC` like so:

``=TRUNC(DATEDIF(start_date, end_date, "M")/3)``

The `TRUNC` function just removes any decimal portion from your result, therefore if used in cell `C3` in the spreadsheet above instead of producing a result of `7.6666667` it would just produce `7`.

## Benefits of `DATEDIF` Over Subtracting Two Dates

An objection to using the `DATEDIF` formula is that it achieves the same result when subtracting dates, which is certainly far simpler than trying to remember a formula, and it’s parameter values.

The biggest benefit of the `DATEDIF` formula is that it helps to calculate the difference between two dates (such as finding someone’s age) by providing us with the type difference we need. Therefore, the `DATEDIF` formula is more versatile for various use cases.

Another minor benefit to using the `DATEDIF` function when calculating the difference in days between two dates over the simple subtraction method is if the input dates contain time.

You can still achieve the same answer as the `DATEDIF` function, but you would need to remember and apply to use the `TRUNC` formula to achieve the same answer in row 3 above, like so:

## `DATEDIF` Errors and Problems

There are a couple of things to be mindful of when using the `DATEDIF` function. As already shown above in the `DATEDIF` days examples we had a result on the last row that gave us an error.

If you do get a `#NUM!` error check the parameter values are correct, and the earliest date is the `start_date` value, and the later date is the `end_date` value.

Provided your parameter values have been set correctly, the only other type of error which may cause problems and may not be as obvious is if the locale setting of your dates are not what you anticipated.

### Incorrect `DATEDIF` Locale

If you’re getting an answer which definitely isn’t correct you will want to check the settings of your spreadsheet to ensure it correctly interprets a date field value.

For example, some countries, such as the UK and Australia, have dates set to the following format: `DD/MM/YYYY` whereas other countries, such as Canada and the Unites States, have date values set to the format of: `MM/DD/YYYY`.

Ways to minimise this error occurring would be to quickly check your locale settings are correct before starting a new spreadsheet, or when modifying a spreadsheet.

In a Google Sheet this would be simply going to File > Spreadsheet Settings > Locale – change this to your country.

Another way to check is to input a date that wouldn’t be a date in the other format, for example, try `01/13/2020` and `13/01/2020` – one of these will not work and your `DATEDIF` formula will return a `#VALUE!` error as the date fields entered aren’t actual dates.
In this article, we’ve done a deep dive into the `DATEDIF` formula and seen the results it provided based on different parameter values.
Overall the `DATEDIF` function is a fantastic function to use, and you should look at incorporating it more in your own daily use. If you’d like to learn more about the function in Google Sheets, you can read the documentation.