Short Title: Azure-SQL AutoSizer: Privacy-Aware Performance-Cost SKU Mapping for SQL Migrations Abstract: We introduce Azure-SQL AutoSizer, a novel SKU recommendation engine designed to automate the selection of Azure SQL PaaS targets—including Azure SQL Database and Azure SQL Managed Instance—during on-premises SQL workload migration. Unlike existing tools that require intrusive access to customer data or queries, AutoSizer operates solely on low-level performance counters such as CPU, memory, IOPS, and latency, ensuring GDPR compliance and data privacy. Our approach leverages a price-performance throttling model to generate personalized SKU rankings and integrates Azure customer telemetry to profile workload negotiability across resource dimensions. Deployed within the Azure Data Migration Assistant (DMA) since October 2021, AutoSizer has demonstrated high accuracy—matching 89.4% of SQL DB and 96.7% of SQL MI expert-vetted SKUs—while identifying significant cost-saving opportunities for over-provisioned Azure SQL customers. The system scales to support hundreds of daily migration assessments without compromising transparency or performance adaptability.