> For the complete documentation index, see [llms.txt](https://docs.fabricplan.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.fabricplan.com/documentation/plan/planning-sheets/formula-syntax/date-functions/datediff.md).

# DATEDIFF

The *DATEDIFF* function returns the number of days between two dates. This function is commonly used to calculate durations, intervals, and date differences in reports and planning scenarios.

{% hint style="info" %}

#### Note

The input dates should be in `MM/DD/YYYY` format. References are also accepted as arguments.
{% endhint %}

#### Syntax

```javascript
DATEDIFF(fromDate, toDate)
```

#### Arguments

* `fromDate`: The start date of the interval.
* `toDate`: The end date of the interval.

#### Return value

Returns the number of days between the two dates.

#### Example

```javascript
DATEDIFF(Open Date, Close Date)
```

Calculates the number of days between the *Open Date* and *Close Date* fields. For example, if *Open Date* is `05/22/2026` and *Close Date* is `05/28/2026`, the function returns `6`.

<figure><img src="/files/WAvXMibQK4OhF4EYMJn2" alt=""><figcaption></figcaption></figure>

#### Excel equivalent

[DATEDIF](https://support.microsoft.com/en-us/office/datedif-function-25dba1a4-2812-480b-84dd-8b32a451b35c)


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