Every business holding stock decides how much to order, when to order it, and how much buffer to carry — and most decide it with a static reorder level that's wrong half the year, so cash sits trapped in slow movers while the fast ones stock out. This reads your stock and sales history from a CSV, spreadsheet or ERP export and returns the actual numbers: optimal order quantity per item, the reorder point that accounts for both demand swings and supplier lead-time variability,