What is the data limit of Block Blobs? The articles say Block Blobs support 190.7TiB of data, while the video says up to 4.7TB; why using different units and which is the right number?

Question

See screenshots of the article on top and the video on bottom
Article Source: https://learn.microsoft.com/en-us/training/modules/explore-provision-deploy-non-relational-data-services-azure/2-azure-blob-storage

Video Source (about 45s in): https://learn.microsoft.com/en-us/shows/on-demand-instructor-led-training-series/dp-900-module-3

This question is related to the following Learning Module

Answer 1

Hi Zakery Mizell,
Welcome to Microsoft Q&A Forum, thank you for posting your query here!
The discrepancy between the data limits for Block Blobs in Azure Blob Storage arises from different versions of the service and the units used.

1. Article (190.7 TiB):
   • The article mentions that Block Blobs can support up to 190.7 TiB. This is based on the maximum block size of 4000 MiB and the maximum number of blocks per blob, which is 50,0001. This calculation is: [ 4000 \text{ MiB/block} \times 50,000 \text{ blocks} = 200,000,000 \text{ MiB} \approx. 190.7 \text{ TiB} ]
   Video (4.7 TB):
   • The video states that Block Blobs can be up to 4.7 TB. This likely refers to an older version of the service where the maximum block size was 100 MiB2. The calculation for this is: [ 100 \text{ MiB/block} \times 50,000 \text{ blocks} = 5,000,000 \text{ MiB} \approx 4.7 \text{ TB} ]

The correct and current limit for Block Blobs in Azure Blob Storage is **190.7 TiB,**The video likely references an outdated limit, which is why there is a difference.
For more information:
https://learn.microsoft.com/en-us/azure/storage/blobs/scalability-targets
https://learn.microsoft.com/en-us/rest/api/storageservices/understanding-block-blobs--append-blobs--and-page-blobs

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