Pricing information for managed disks can be found here.
We charge $0.002 per 10,000 transaction units for Standard SSD Managed Disks. Any type of operation against the storage is counted as a transaction, including reads, writes and deletes. We use IO unit size of 256 KiB for counting the billable transaction units. Please refer to Standard SSD documentation for more information.
If you still find any difficulties in understanding, Free billing and subscription management support is provided. The Billing and Subscription team would be the best to provide more insight and guidance on the pricing.
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