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--- title: Create a parameters file for bicep deployment description: Learn how to create Bicep parameters files instead of passing parameters as inline values in your script. ms.topic: how-to ms.custom: devx-track-bicep ms.date: 12/03/2025 --- # Create a parameters file for Bicep deployment Bicep parameter files allow you to define values in an individual file that are then passed to your `main.bicep` file. The parameter file exposes values that may change from a given subscription, environment, and/or region. Leveraging a parameter file will drive consistency in your IaC deployments while also providing flexibility. Some of this flexibility might allow an organization to take advantage of cost benefits by right-sizing their nonproduction environments while maintaining the same core infrastructure. These parameter files also help enable a streamlined CI/CD deployment approach. Each parameter file is under source control and passed into the appropriate automated deployment steps. These parameter files ensure a consistent deployment experience. This article shows you how to create a parameters file, which you can use instead of passing parameters as inline values in your script. You can use either a Bicep parameters file with the `.bicepparam` file extension or a JSON parameters file that contains the parameter value. > [!NOTE] > Bicep parameters files are supported only in [Bicep CLI version 0.18.4](https://github.com/Azure/bicep/releases/tag/v0.18.4) or later, [Azure CLI](/cli/azure/install-azure-cli) version 2.47.0 or later, and [Azure PowerShell](/powershell/azure/install-azure-powershell) version 9.7.1 or later. The `using none` feature is supported in [Bicep CLI version 0.31.0](https://github.com/Azure/bicep/releases/tag/v0.31.92) or later. A single Bicep file can be associated with multiple parameter files. However, each parameter file is typically linked to one specific Bicep file—unless `using none` is specified. This association is established using the [`using` statement](./bicep-using.md) within the parameter file. You can compile Bicep parameters files into JSON parameters files that you can deploy by using a Bicep file. For more information, see [`build-params`](./bicep-cli.md#build-params). You can also decompile a JSON parameters file into a Bicep parameters file. For more information, see [`decompile-params`](./bicep-cli.md#decompile-params). ## Parameters file A parameters file uses the following format: ### [Bicep parameters file](#tab/Bicep) ```bicep using '<path>/<file-name>.bicep' | using none type <user-defined-data-type-name> = <type-expression> var <variable-name> <data-type> = <variable-value> param <first-parameter-name> = <first-value> param <second-parameter-name> = <second-value> param <third-parameter-name> = <variable-name> ``` You can apply the `using` statement by using a Bicep file, JSON Azure Resource Manager templates, Bicep modules, and template specifications. For example: ```bicep using './main.bicep' ... ``` ```bicep using './azuredeploy.json' ... ``` ```bicep using 'br/public:avm/res/storage/storage-account:0.9.0' ... ``` ```bicep using 'br:myacr.azurecr.io/bicep/modules/storage:v1' ... ``` ```bicep using 'ts:00000000-0000-0000-0000-000000000000/myResourceGroup/storageSpec:1.0' ... ``` For more information, see [Using statement](./bicep-using.md#the-using-statement). You can apply the `using none` statement to indicate that the parameters file is not tied to a specific Bicep template during authoring or compilation. This decouples the parameter file from a particular template, enabling greater flexibility in how parameters are defined and used across deployments. For more information, see [Using none statement](./bicep-using.md#the-using-none-statement). You can use expressions as parameter values. For example: ```bicep using './main.bicep' param storageName = toLower('MyStorageAccount') param intValue = 2 + 2 ``` You can reference environment variables as parameter values. For example: ```bicep using './main.bicep' param intFromEnvironmentVariables = int(readEnvironmentVariable('intEnvVariableName')) ``` You can define and use variables. You must use [Bicep CLI](./install.md#visual-studio-code-and-bicep-extension) version 0.21.X or later to use variables in `.bicepparam` files. See the following examples: ```bicep using './main.bicep' var storagePrefix = 'myStorage' param primaryStorageName = '${storagePrefix}Primary' param secondaryStorageName = '${storagePrefix}Secondary' ``` ```bicep using './main.bicep' var testSettings = { instanceSize: 'Small' instanceCount: 1 } var prodSettings = { instanceSize: 'Large' instanceCount: 4 } param environmentSettings = { test: testSettings prod: prodSettings } ``` You can define user-defined data types. For example: ```bicep using './main.bicep' // Define a reusable type for tags with optional properties type TagValues = { environment: 'dev' | 'test' | 'production' project: string } var tagsExample TagValues = { environment: 'dev' project: 'bicep-sample' } param tags = tagsExample ``` ### [JSON parameters file](#tab/JSON) ```json { "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentParameters.json#", "contentVersion": "1.0.0.0", "parameters": { "<first-parameter-name>": { "value": "<first-value>" }, "<second-parameter-name>": { "value": "<second-value>" } } } ``` --- > [!NOTE] > A parameters file saves parameter values as plain text. For security reasons, we don't recommend using this approach with sensitive values such as passwords. If you need to pass a parameter with a sensitive value, you should keep the value in a key vault. Instead of adding a sensitive value to your parameters file, use the [`getSecret` function](bicep-functions-resource.md#getsecret) to retrieve it. For more information, see [Use Azure Key Vault to pass a secret as a parameter during Bicep deployment](key-vault-parameter.md). ## Parameter type formats The following example shows the formats of various parameter types: string, integer, Boolean, array, and object. ### [Bicep parameters file](#tab/Bicep) ```bicep using './main.bicep' param exampleString = 'test string' param exampleInt = 2 + 2 param exampleBool = true param exampleArray = [ 'value 1' 'value 2' ] param exampleObject = { property1: 'value 1' property2: 'value 2' } ``` Use Bicep syntax to declare [objects](./data-types.md#objects) and [arrays](./data-types.md#arrays). ### [JSON parameters file](#tab/JSON) ```json { "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentParameters.json#", "contentVersion": "1.0.0.0", "parameters": { "exampleString": { "value": "test string" }, "exampleInt": { "value": 4 }, "exampleBool": { "value": true }, "exampleArray": { "value": [ "value 1", "value 2" ] }, "exampleObject": { "value": { "property1": "value1", "property2": "value2" } } } } ``` --- ## File name ### [Bicep parameters file](#tab/Bicep) The file extension for a Bicep parameters file is `.bicepparam`. To deploy to multiple environments, you create more than one parameters file. When you use multiple parameters files, label them according to their use. For example, to deploy resources, use the label _main.dev.bicepparam_ for development and the label _main.prod.bicepparam_ for production. ### [JSON parameters file](#tab/JSON) The general naming convention for a parameters file is to include _parameters_ in the Bicep file name. For example, if your Bicep file is named _azuredeploy.bicep_, then your parameters file is named _azuredeploy.parameters.json_. This naming convention helps you see the connection between the Bicep file and the parameters. To deploy to different environments, you create more than one parameters file. When you use multiple parameters files, label them according to their use. For example, to deploy resources, use the label _azuredeploy.parameters-dev.json_ for development and the label _azuredeploy.parameters-prod.json_ for production. --- ## Define parameter values To determine how to define parameter names and values, open your Bicep file. Look at the **parameters** section of the Bicep file. The following examples show the parameters from a Bicep file named `main.bicep`: ```bicep @maxLength(11) param storagePrefix string @allowed([ 'Standard_LRS' 'Standard_GRS' 'Standard_ZRS' 'Premium_LRS' ]) param storageAccountType string = 'Standard_LRS' ``` In the parameters file, look for the name of each parameter. The parameter names in your parameters file must match the parameter names in your Bicep file. ### [Bicep parameters file](#tab/Bicep) ```bicep using 'main.bicep' param storagePrefix param storageAccountType ``` The `using` statement ties the Bicep parameters file to a Bicep file. For more information, see [Using statement](./bicep-using.md). When you type the keyword `param` in Visual Studio Code, it prompts you the available parameters and their descriptions from the linked Bicep file. :::image type="content" source="./media/parameter-files/bicep-parameters-file-visual-studio-code-prompt.png" alt-text="Screenshot of the prompt of the available parameters."::: When you hover over a `param` name, you can see the parameter data type and description. :::image type="content" source="./media/parameter-files/bicep-parameters-file-visual-studio-code-hover.png" alt-text="Screenshot of the parameter data type and description."::: ### [JSON parameters file](#tab/JSON) ```json { "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentParameters.json#", "contentVersion": "1.0.0.0", "parameters": { "storagePrefix": { }, "storageAccountType": { } } } ``` --- Review the parameter type, because the parameter types in your parameters file must use the same types as your Bicep file. In this example, both parameter types are strings: ### [Bicep parameters file](#tab/Bicep) ```bicep using 'main.bicep' param storagePrefix = '' param storageAccountType = '' ``` ### [JSON parameters file](#tab/JSON) ```json { "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentParameters.json#", "contentVersion": "1.0.0.0", "parameters": { "storagePrefix": { "value": "" }, "storageAccountType": { "value": "" } } } ``` --- Check the Bicep file for parameters that include a default value. If a parameter has a default value, you can provide a value in the parameters file, but it isn't required. The parameters file value overrides the Bicep file's default value. ### [Bicep parameters file](#tab/Bicep) ```bicep using 'main.bicep' param storagePrefix = '' // This value must be provided. param storageAccountType = '' // This value is optional. Bicep uses default value if not provided. ``` ### [JSON parameters file](#tab/JSON) ```json { "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentParameters.json#", "contentVersion": "1.0.0.0", "parameters": { "storagePrefix": { "value": "" // This value must be provided. }, "storageAccountType": { "value": "" // This value is optional. Bicep uses default value if not provided. } } } ``` > [!NOTE] > For inline comments, you can use either // or /* ... */. In Visual Studio Code, save parameters files with the `JSONC` file type. If you don't, you get an error message that says, "Comments not permitted in JSON." --- To see if there are any restrictions like maximum length, check the Bicep file's allowed values. The allowed values specify the range of values you can provide for a parameter. In this example, `storagePrefix` can have a maximum of 11 characters, and `storageAccountType` must specify an allowed value. ### [Bicep parameters file](#tab/Bicep) ```bicep using 'main.bicep' param storagePrefix = 'storage' param storageAccountType = 'Standard_ZRS' ``` ### [JSON parameters file](#tab/JSON) ```json { "$schema": "https://schema.management.azure.com/schemas/2019-04-01/deploymentParameters.json#", "contentVersion": "1.0.0.0", "parameters": { "storagePrefix": { "value": "storage" }, "storageAccountType": { "value": "Standard_ZRS" } } } ``` > [!NOTE] > Your parameters file can contain only values for parameters that are defined in the Bicep file. If your parameters file contains extra parameters that don't match the Bicep file's parameters, you receive an error. --- ## Generate parameters file You can create a parameters file by using either Visual Studio Code or the Bicep CLI. Both tools allow you to use a Bicep file to generate a parameters file. See [Generate parameters file](./visual-studio-code.md#generate-parameters-file-command) for the Visual Studio Code method and [Generate parameters file](./bicep-cli.md#generate-params) for the Bicep CLI method. ## Build Bicep parameters file From the Bicep CLI, you can build a Bicep parameters file into a JSON parameters file. For more information, see [Build parameters file](./bicep-cli.md#build-params). ## Deploy Bicep file with parameters file ### Azure CLI From the Azure CLI, you can pass a parameters file with your Bicep file deployment. ### [Bicep parameters file](#tab/Bicep) You can deploy a Bicep file by using a Bicep parameters file with [Azure CLI](./install.md#azure-cli) version 2.53.0 or later and [Bicep CLI](./install.md#visual-studio-code-and-bicep-extension) version 0.22.X or later. With the `using` statement within the Bicep parameters file, there's no need to provide the `--template-file` switch when specifying a Bicep parameters file for the `--parameters` switch. ```azurecli az deployment group create \ --name ExampleDeployment \ --resource-group ExampleGroup \ --parameters storage.bicepparam ``` ### [JSON parameters file](#tab/JSON) ```azurecli az deployment group create \ --name ExampleDeployment \ --resource-group ExampleGroup \ --template-file storage.bicep \ --parameters storage.parameters.json ``` --- You can use inline parameters and a location parameters file in the same deployment operation. For example: ### [Bicep parameters file](#tab/Bicep) ```azurecli az deployment group create \ --name ExampleDeployment \ --resource-group ExampleGroup \ --parameters storage.bicepparam \ --parameters storageAccountType=Standard_LRS ``` ### [JSON parameters file](#tab/JSON) ```azurecli az deployment group create \ --name ExampleDeployment \ --resource-group ExampleGroup \ --template-file storage.bicep \ --parameters storage.parameters.json \ --parameters storageAccountType=Standard_LRS ``` --- For more information, see [Deploy Bicep files by using the Azure CLI](./deploy-cli.md#parameters). ### Azure PowerShell From Azure PowerShell, pass a local parameters file by using the `TemplateParameterFile` parameter. ### [Bicep parameters file](#tab/Bicep) ```azurepowershell New-AzResourceGroupDeployment ` -Name ExampleDeployment ` -ResourceGroupName ExampleResourceGroup ` -TemplateFile C:\MyTemplates\storage.bicep ` -TemplateParameterFile C:\MyTemplates\storage.bicepparam ``` ### [JSON parameters file](#tab/JSON) ```azurepowershell New-AzResourceGroupDeployment ` -Name ExampleDeployment ` -ResourceGroupName ExampleResourceGroup ` -TemplateFile C:\MyTemplates\storage.bicep ` -TemplateParameterFile C:\MyTemplates\storage.parameters.json ``` --- You can use inline parameters and a location parameters file in the same deployment operation. For example: ### [Bicep parameters file](#tab/Bicep) ```azurepowershell New-AzResourceGroupDeployment ` -Name ExampleDeployment ` -ResourceGroupName ExampleResourceGroup ` -TemplateFile C:\MyTemplates\storage.bicep ` -TemplateParameterFile C:\MyTemplates\storage.bicepparam ` -storageAccountType Standard_LRS ``` ### [JSON parameters file](#tab/JSON) ```azurepowershell New-AzResourceGroupDeployment ` -Name ExampleDeployment ` -ResourceGroupName ExampleResourceGroup ` -TemplateFile C:\MyTemplates\storage.bicep ` -TemplateParameterFile C:\MyTemplates\storage.parameters.json ` -storageAccountType Standard_LRS ``` --- For more information, see [Deploy Bicep files with Azure PowerShell](./deploy-powershell.md#parameters). To deploy `.bicep` files, you need Azure PowerShell version 5.6.0 or later. ## Parameter precedence You can use inline parameters and a local parameters file in the same deployment operation. For example, you can specify some values in the local parameters file and add other values inline during deployment. If you provide values for a parameter in both the local parameters file and inline, the inline value takes precedence. Although external Bicep parameters files aren't currently supported, you can use an external JSON parameters file by providing the URI to the file. When you use an external parameters file, provide all parameter values in the external file. When you use an external file, you can't pass other values inline or from a local file, and all inline parameters are ignored. ## Parameter name conflicts If your Bicep file includes a parameter with the same name as one of the parameters in the Azure PowerShell command, Azure PowerShell presents the parameter from your Bicep file with the `FromTemplate` postfix. For example, if a parameter named `ResourceGroupName` in your Bicep file conflicts with the `ResourceGroupName` parameter in the [`New-AzResourceGroupDeployment` cmdlet](/powershell/module/az.resources/new-azresourcegroupdeployment), you're prompted to provide a value for `ResourceGroupNameFromTemplate`. To avoid this confusion, use parameter names that aren't used for deployment commands. ## Related content - For more information about how to define parameters in a Bicep file, see [Parameters in Bicep](./parameters.md). - To get sensitive values, see [Use Azure Key Vault to pass secure parameter value during deployment](./key-vault-parameter.md).