# NULL functions

This section describes functions for returning or detecting NULL values.

All functions can be used in both the load script and in chart expressions.

Use the drop-down on each function to see a brief description and the syntax of each function. Click the function name in the syntax description for further details.

[](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/Scripting/NULLFunctions/null-functions.htm)

#### Null

The Null function returns a NULL value.

[**Null**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/Scripting/NULLFunctions/Null.htm)( )

[](https://help.qlik.com/en-US/qlikview/Subsystems/Client/Content/QV_QlikView/Scripting/NULLFunctions/null-functions.htm)

#### IsNull

The IsNull function tests if the value of an expression is NULL and if so, returns -1 (True), otherwise 0 (False).

[**IsNull**](https://help.qlik.com/en-US/qlikview/September2026/Subsystems/Client/Content/QV_QlikView/Scripting/NULLFunctions/IsNull.htm)(expr )