> ## Documentation Index
> Fetch the complete documentation index at: https://www.integrate.io/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# ETL: WeeksBetween

> Calculate the number of weeks between two datetime values. Use WEEKSBETWEEN for weekly period analysis and reporting in ETL pipeline expressions.

## Description

Returns the number of weeks between the end\_datetime and the start\_datetime.

## Syntax

`WeeksBetween(end_datetime, start_datetime)`

## Arguments

*end\_datetime* - datetime expression.

*start\_datetime* - datetime expression.

## Examples

`WeeksBetween(ToDate('2013-09-10T08:02:31.667Z'),ToDate('2012-03-03T13:34:39.648Z'))` returns 79

## Return value datatype

Long

## Impact of null value

If input is null, returns null.