Compared: Azure Blob Storage tiers - Hot, Cool, & Archive (preview) storage

Tabular summary of the article Azure Blob Storage: Hot, cool, and archive (preview) storage tiers

To manage costs for your expanding storage needs, it's helpful to organize your data based on attributes like frequency-of-access and planned retention period. With hot, cool, and archive storage tiers, Azure Blob storage addresses this need for differentiated storage tiers with separate pricing models.

Blob Storage Accounts are specialized storage accounts for storing your unstructured data as blobs (objects) in Azure Storage distinct from General Purpose Storage Account. You cannot convert an existing storage account to a Blob storage account

Blob storage accounts cannot be used to store virtual machine disks or page blobs.

Going forward, Blob storage accounts are the recommended way for storing blobs

	Hot storage tier	Cool storage tier	Archive storage tier
Purpose	for storing data that is accessed frequently	for storing data that is infrequently accessed and stored for at least a month	for storing data that is rarely accessed and stored for at least six months with flexible latency requirements (on the order of hours).
Usage Scenarios	Data that is in active use or expected to be accessed (read from and written to) frequently. Data that is staged for processing and eventual migration to the cool storage tier.	Short-term backup and disaster recovery datasets. Older media content not viewed frequently anymore but is expected to be available immediately when accessed. Large data sets that need to be stored cost effectively while more data is being gathered for future processing. (For example, long-term storage of scientific data, raw telemetry data from a manufacturing facility)	Long-term backup, archival, and disaster recovery datasets Original (raw) data that must be preserved, even after it has been processed into final usable form. (For example, Raw media files after transcoding into other formats) Compliance and archival data that needs to be stored for a long time and is hardly ever accessed. (For example, Security camera footage, old X-Rays/MRIs for healthcare organizations, audio recordings, and transcripts of customer calls for financial services)
Availability	99.9%	99%	currently no SLA
Availability (RA-GRS reads)	99.99%	99.9%
Usage charges	Higher storage costs, lower access and transaction costs	Lower storage costs, higher access and transaction costs	Lowest storage cost and higher data retrieval costs compared to hot and cool storage.
Minimum object size	N/A	N/A
Minimum storage duration	N/A	N/A
Latency (Time to first byte)	milliseconds	milliseconds	on the order of hours?
Scalability and performance targets	Same as general-purpose storage accounts	Same as general-purpose storage accounts