The need for storage capacity is growing significantly in most organisations. The increase is driven by everything from greater use of images, video, sensor data and AI to stricter requirements for backup, security and compliance. At the same time, storage is one of the IT areas where even relatively small changes in data volumes can have significant financial implications. For organisations focused on IT economics, budgeting and long-term capacity planning, it is therefore essential to take a structured approach to analysing and forecasting storage requirements.

A systematic storage capacity analysis provides a quantitative basis for understanding both organic data growth and the growth driven by upcoming business initiatives. The analysis makes it possible to translate technical factors into financial implications, thereby creating a shared basis for dialogue between IT and the business, and can be used as a basis for decisions on investments, sourcing choices or adjustments to data and storage policies.

In this article, we present a method for analysing and forecasting the organisation’s total storage capacity requirements 3–5 years ahead, broken down by systems, data types and sourcing models. The method can be used as a foundation for IT budgeting, future infrastructure investments and strategic storage decisions.