How do I size my requirement for Azure SQL PaaS?

Azure SQL PaaS offerings are based on DTU (Database Transaction Units). A DTU is a blended measure of CPU, memory and I/O. A study of existing resource consumption in the database on-premises will provide a measure of DTU requirements based on which the partner can choose the appropriate offering level.

Refer to guidance on DTU and analysis here . To gain deeper insight into the resource (DTU) consumption of your workload, use Azure SQL Database Query Performance Insight