@Awangku Faiz Welcome to Microsoft Q&A Forum, Thank you for posting your query here!
Go to Cost management + Billing option and portal ->Add filter -> microsoft.storage/storageaccount -> RG name & Groupby resource. as show in the below image.
Cold tier pricing is positioned between cool and archive, with 90-day early deletion policy. See the prices in Azure Blob Storage pricing. You can seamlessly use the cold tier the way you use hot and cool, through REST API, SDK, tools, and lifecycle management policy.
You can also refer to this threads for more information on Azure Storage.
archive storage cost concepts
How to get detailed reports on Azure archive Storage Billing
The cost to store for archive storage.
You can calculate the storage costs by multiplying the size of the data in GB by the price of archive storage.
For example (assuming the sample pricing), if you plan to store 10 TB archived blobs, the capacity cost is $0.00099 * 10 * 1024 = $10.14 per month.
If you still have any question I would recommened to contact Azure Billing and Subscription team would be the best to provide more insight and guidance on this scenario based on your region and requirements. It's a Free support and best option for you.
https://azure.microsoft.com/en-us/support/options/
Please let us know if you have any further queries. I’m happy to assist you further.
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