Optimizing Inventory Flow for Business Efficiency
The Days Sales in Inventory (DSI) Calculator measures how quickly a company converts inventory into sales. It calculates DSI, inventory turnover, and daily COGS, providing critical insights into operational efficiency and working capital management. For many businesses in 2026, a DSI between 30 and 60 days is considered healthy, reflecting a balance between having sufficient stock and minimizing holding costs.
The Days Sales in Inventory Calculation Explained
Days Sales in Inventory is calculated by dividing ending inventory by COGS, then multiplying by the number of days in the period.
days sales in inventory = (ending inventory / cost of goods sold) x days in period
inventory turnover = cost of goods sold / ending inventory
daily COGS = cost of goods sold / days in period
For instance, with $50,000 in ending inventory, COGS of $200,000, and a 365-day period: DSI = ($50,000 / $200,000) x 365 = 91.25 days. The inventory turnover is $200,000 / $50,000 = 4.00x.
Calculating Inventory Turnover for a Retailer
Let's apply the DSI calculation:
- Ending Inventory: $50,000
- Cost of Goods Sold (COGS): $200,000 (annual)
- Days in Period: 365 days
Calculate Days Sales in Inventory (DSI):
DSI = ($50,000 / $200,000) x 365 = 0.25 x 365 = 91.25 days
Determine Inventory Turnover:
Inventory Turnover = $200,000 / $50,000 = 4.00x
Calculate Daily COGS:
Daily COGS = $200,000 / 365 = $548
Calculate Inventory-to-COGS Ratio:
Ratio = ($50,000 / $200,000) x 100 = 25.0%
This business holds approximately 91.25 days of sales in inventory, with a turnover of 4x per year. The 25% inventory-to-COGS ratio indicates a moderate stock level relative to annual cost of sales.
DSI Benchmarks Across Key Industries
DSI benchmarks vary widely due to differing product life cycles, demand volatility, and supply chain complexities:
- Fast-moving consumer goods (FMCG) and grocery: 15-30 days. Products are highly perishable, requiring lean management.
- General retail (clothing, electronics): 45-75 days. Balances seasonal demand with holding costs.
- Manufacturing (automotive, heavy machinery): 90-150 days. Complex supply chains require larger inventories.
- Luxury goods or specialized equipment: 180+ days. Niche markets with slower turnover but higher margins.
Understanding these benchmarks helps assess whether your DSI of 91.25 days is appropriate for your sector in 2026.
DSI as Part of the Cash Conversion Cycle
DSI is one component of the Cash Conversion Cycle (CCC = DSI + DSO - DPO). A lower DSI reduces the CCC, meaning faster cash recovery from inventory investments. Combining DSI analysis with accounts receivable (DSO) and accounts payable (DPO) metrics provides a complete picture of working capital efficiency.
