Hi Niket Kumar Singh •,
The Azure Cosmos DB free tier is compatible with the Azure free account. To opt in, create an Azure Cosmos DB free tier account in your Azure free account subscription. For the first 12 months, you'll get a combined discount of 1400 RU/s (1000 RU/s from Azure Cosmos DB free tier and 400 RU/s from Azure free account) and 50 GB of storage (25 GB from Azure Cosmos DB free tier and 25 GB from Azure free account). After the 12 months expire, you'll continue to get 1000 RU/s and 25 GB from the Azure Cosmos DB free tier, for the lifetime of the Azure Cosmos DB account. For an example of how the charges are stacked, see Billing examples with free tier accounts.
Note
Azure Cosmos DB free tier is different from the Azure free account. The Azure free account offers Azure credits and resources for free for a limited time. When using Azure Cosmos DB as a part of this free account, you get 25-GB storage and 400 RU/s of provisioned throughput for 12 months.
You can create a free tier account from the Azure portal, PowerShell, CLI, or Azure Resource Manager (ARM) templates. You can choose free tier while creating the account, you can’t set it after the account is created.
If you create an account with free tier and then delete it, you can apply free tier for a new account. When creating a new account.
Thanks