| Base Of Difference | Azure Scale Sets | Azure Availability Sets |
| Definition | This is a group of identical configured VMs which are spread across multiple fault domains. | This is a group of discreate configured VMs which spread across various fault domains. |
| Count of VM | Here we can increased and decreased based on demand or any of pre-defined schedule. | Here we can add VM to availability set only ate time of set's creation. |
| Default Domain | Here we have 5 Fault Domains and update domains by default | Here we have 3 Fault domains and 5 Update domains. |
| Style Distribution | Here VM scale sets be distributed across multiple data centers or within a single data center. | Here VM are automatically distributed in a data center. |
| Type of Workload | Here we used when we have some unpredictable workloads which require the feature of auto scalability. | It is oppposite of Azure Scale Sets here these are used when we have predictable workload requirements. |
| Style of Configuration | Here VMs are configured and created in same manner from the same image. | Here VMs are created by making use of different images and configurations. |