SQL Server Growth Calculator accuracy and testing

Formula source

• Projected data GB = current data GB + monthly growth GB * months. Total = projected data * (1 + log percent + index overhead percent + free-space buffer percent).

Test cases

Known limitations

• This page documents the checked-in calculator logic and does not certify results for every real-world edge case.
• Use the result as a planning estimate unless the calculator page states a stricter purpose.

Assumptions

• Growth is modeled linearly from user-entered assumptions.
• The calculator does not inspect SQL Server metadata, compression, filegroups, tempdb, HA replicas, or backup storage.
• Results are for capacity planning only and run locally.

Unit handling

• Current Data Size accepts values in GB.
• Monthly Growth accepts values in GB/mo.
• Forecast Horizon accepts values in months.
• Transaction Log Allowance accepts values in %.
• Index Overhead accepts values in %.
• Free-Space Buffer accepts values in %.
• Projected Storage Need is displayed in GB.
• Projected Data Size is displayed in GB.
• Log Allowance is displayed in GB.
• Overhead and Buffer is displayed in GB.

Rounding rules

• Number displays use up to 2 decimal places in the calculator UI.
• Input precision follows configured step values where provided.

Version history

Change log