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title Template functions - logical
description Describes the functions to use in an Azure Resource Manager template (ARM template) to determine logical values.
ms.topic reference
ms.custom devx-track-arm-template
ms.date 08/01/2025

Logical functions for ARM templates

Resource Manager provides several functions for making comparisons in your Azure Resource Manager template (ARM template):

Tip

Bicep is recommended since it offers the same capabilities as ARM templates, and the syntax is easier to use. To learn more, see the bool logical function and logical operators.

and

and(arg1, arg2, ...)

Checks if all parameter values are true.

The and function isn't supported in Bicep. Use the && operator instead.

Parameters

Parameter Required Type Description
arg1 Yes boolean The first value to check if it's true.
arg2 Yes boolean The second value to check if it's true.
more arguments No boolean More arguments to check if they're true.

Return value

Returns True if all values are true; otherwise, False.

Examples

The following example shows how to use the logical function:

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "resources": [],
  "outputs": {
    "andExampleOutput": {
      "type": "bool",
      "value": "[and(bool('true'), bool('false'))]"
    },
    "orExampleOutput": {
      "type": "bool",
      "value": "[or(bool('true'), bool('false'))]"
    },
    "notExampleOutput": {
      "type": "bool",
      "value": "[not(bool('true'))]"
    }
  }
}

The output from the preceding example is:

Name Type Value
andExampleOutput Bool False
orExampleOutput Bool True
notExampleOutput Bool False

bool

bool(arg1)

Converts the parameter to a boolean.

In Bicep, use the bool logical function.

Parameters

Parameter Required Type Description
arg1 Yes string or int The value to convert to a boolean.

Return value

A boolean of the converted value.

Remarks

You can also use true() and false() to get boolean values.

Examples

The following example shows how to use bool with a string or an integer:

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "resources": [],
  "outputs": {
    "trueString": {
      "type": "bool",
      "value": "[bool('true')]"
    },
    "falseString": {
      "type": "bool",
      "value": "[bool('false')]"
    },
    "trueInt": {
      "type": "bool",
      "value": "[bool(1)]"
    },
    "falseInt": {
      "type": "bool",
      "value": "[bool(0)]"
    }
  }
}

The output of default values from the preceding example is:

Name Type Value
trueString Bool True
falseString Bool False
trueInt Bool True
falseInt Bool False

false

false()

Returns false.

The false function isn't available in Bicep. Use the false keyword instead.

Parameters

The false function doesn't accept any parameters.

Return value

A boolean that's always false.

Example

The following example returns a false output value:

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "resources": [],
  "outputs": {
    "falseOutput": {
      "type": "bool",
      "value": "[false()]"
    }
  }
}

The output from the preceding example is:

Name Type Value
falseOutput Bool False

if

if(condition, trueValue, falseValue)

Returns a value based on if a condition is true or false.

The if function isn't supported in Bicep. Use the ?: operator instead.

Parameters

Parameter Required Type Description
condition Yes boolean The value to check if it's true or false.
trueValue Yes string, int, object, or array The value to return when the condition is true.
falseValue Yes string, int, object, or array The value to return when the condition is false.

Return value

Returns second parameter when first parameter is True; otherwise, returns third parameter.

Remarks

When the condition is True, only the true value is evaluated. When the condition is False, only the false value is evaluated. With the if function, you can include expressions that are only conditionally valid. For example, you can reference a resource that exists under one condition but not under the other condition. An example of conditionally evaluating expressions is shown in the following section.

Note that the above rule only applies when the condition can be evaluated at the start of the template deployment process. For instance, you can't use a reference() in the condition.

Examples

The following example shows how to use the if function:

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "resources": [
  ],
  "outputs": {
    "yesOutput": {
      "type": "string",
      "value": "[if(equals('a', 'a'), 'yes', 'no')]"
    },
    "noOutput": {
      "type": "string",
      "value": "[if(equals('a', 'b'), 'yes', 'no')]"
    },
    "objectOutput": {
      "type": "object",
      "value": "[if(equals('a', 'a'), json('{\"test\": \"value1\"}'), json('null'))]"
    }
  }
}

The output from the preceding example is:

Name Type Value
yesOutput String yes
noOutput String no
objectOutput Object { "test": "value1" }

The following example template shows how to use this function with expressions that are only conditionally valid.

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "parameters": {
    "vmName": {
      "type": "string"
    },
    "location": {
      "type": "string"
    },
    "logAnalytics": {
      "type": "string",
      "defaultValue": ""
    }
  },
  "resources": [
   {
      "condition": "[not(empty(parameters('logAnalytics')))]",
      "type": "Microsoft.Compute/virtualMachines/extensions",
      "apiVersion": "2025-04-01",
      "name": "[format('{0}/omsOnboarding', parameters('vmName'))]",
      "location": "[parameters('location')]",
      "properties": {
        "publisher": "Microsoft.EnterpriseCloud.Monitoring",
        "type": "MicrosoftMonitoringAgent",
        "typeHandlerVersion": "1.0",
        "autoUpgradeMinorVersion": true,
        "settings": {
          "workspaceId": "[if(not(empty(parameters('logAnalytics'))), reference(parameters('logAnalytics'), '2015-11-01-preview').customerId, null())]"
        },
        "protectedSettings": {
          "workspaceKey": "[if(not(empty(parameters('logAnalytics'))), listKeys(parameters('logAnalytics'), '2015-11-01-preview').primarySharedKey, null())]"
        }
      }
    }
  ],
  "outputs": {
    "mgmtStatus": {
      "type": "string",
      "value": "[if(not(empty(parameters('logAnalytics'))), 'Enabled monitoring for VM!', 'Nothing to enable')]"
    }
  }
}

not

not(arg1)

Converts boolean value to its opposite value.

The not function isn't supported in Bicep. Use the ! operator instead.

Parameters

Parameter Required Type Description
arg1 Yes boolean The value to convert.

Return value

Returns True when parameter is False. Returns False when parameter is True.

Examples

The following example shows how to use the logical function:

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "resources": [],
  "outputs": {
    "andExampleOutput": {
      "type": "bool",
      "value": "[and(bool('true'), bool('false'))]"
    },
    "orExampleOutput": {
      "type": "bool",
      "value": "[or(bool('true'), bool('false'))]"
    },
    "notExampleOutput": {
      "type": "bool",
      "value": "[not(bool('true'))]"
    }
  }
}

The output from the preceding example is:

Name Type Value
andExampleOutput Bool False
orExampleOutput Bool True
notExampleOutput Bool False

The following example uses not with equals:

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "resources": [
  ],
  "outputs": {
    "checkNotEquals": {
      "type": "bool",
      "value": "[not(equals(1, 2))]"
    }
  }
}

The output from the preceding example is:

Name Type Value
checkNotEquals Bool True

or

or(arg1, arg2, ...)

Checks if any parameter value is true.

The or function isn't supported in Bicep. Use the || operator instead.

Parameters

Parameter Required Type Description
arg1 Yes boolean The first value to check if it's true.
arg2 Yes boolean The second value to check if it's true.
more arguments No boolean More arguments to check if they're true.

Return value

Returns True if any value is true; otherwise, False.

Examples

The following example shows how to use the logical function:

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "resources": [],
  "outputs": {
    "andExampleOutput": {
      "type": "bool",
      "value": "[and(bool('true'), bool('false'))]"
    },
    "orExampleOutput": {
      "type": "bool",
      "value": "[or(bool('true'), bool('false'))]"
    },
    "notExampleOutput": {
      "type": "bool",
      "value": "[not(bool('true'))]"
    }
  }
}

The output from the preceding example is:

Name Type Value
andExampleOutput Bool False
orExampleOutput Bool True
notExampleOutput Bool False

true

true()

Returns true.

The true function isn't available in Bicep. Use the true keyword instead.

Parameters

The true function doesn't accept any parameters.

Return value

A boolean that's always true.

Example

The following example returns a true output value:

{
  "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentTemplate.json#",
  "contentVersion": "1.0.0.0",
  "resources": [],
  "outputs": {
    "trueOutput": {
      "type": "bool",
      "value": "[true()]"
    }
  }
}

The output from the preceding example is:

Name Type Value
trueOutput Bool True

Next steps