How to Use This Calculator
- 1
Enter Ending Inventory
Input the monetary value of inventory on hand at the end of your accounting period.
- 2
Specify Cost of Goods Sold (COGS)
Provide the total cost of goods sold during the same accounting period.
- 3
Define Days in Period
Enter the number of days in the period you are analyzing (e.g., 365 for annual, 90 for quarterly).
- 4
Review your results
The calculator displays Days Sales in Inventory (DSI), Inventory Turnover, Daily COGS, and Inventory-to-COGS Ratio. The Inventory Efficiency Insights panel shows capital tied up, turnover efficiency analysis, and quarterly/annual equivalents.
Example Calculation
A business wants to calculate its Days Sales in Inventory (DSI) for a year with an ending inventory value of $50,000 and a Cost of Goods Sold (COGS) of $200,000.
Ending Inventory
$50,000
Cost of Goods Sold (COGS)
$200,000
Days in Period
365
Results
Days Sales in Inventory
91.3 days
Inventory Turnover
4.00x
Daily COGS
$548
Inventory-to-COGS Ratio
25.0%
Tips
Compare DSI to Industry Averages
Benchmark your DSI against industry averages. A DSI of 30-60 days is often healthy for retail, while manufacturing might see 90-120 days. A DSI of 91.3 days (as in the example) suggests moderate performance for most retailers.
Track DSI Trends Over Time
Monitor your DSI quarterly and annually in 2026. A rising DSI might signal slowing sales or inefficient inventory management, whereas a falling DSI suggests improved inventory liquidity and operational efficiency.
Optimize for Perishable Goods
For businesses dealing with perishable or rapidly obsolescing inventory (food, fashion, electronics), a very low DSI is crucial to minimize waste and markdown costs. Aim for under 30 days where possible.
Use the Insights Panel
The Inventory Efficiency Insights panel shows how much capital is tied up in inventory and provides turnover benchmarks. If your turnover is below 6x, it suggests room for improvement in stock management.
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.
Frequently Asked Questions
What is Days Sales in Inventory (DSI)?
Days Sales in Inventory (DSI) measures how many days it takes to convert current inventory into sales. It is calculated as (Ending Inventory / COGS) x Days in Period. With $50,000 inventory and $200,000 annual COGS, DSI is 91.3 days — meaning it takes about 3 months to sell through current stock.
How does DSI impact a company's working capital?
DSI indicates how much cash is tied up in inventory. A DSI of 91.3 days means $50,000 is locked in stock for about 3 months before converting to sales. Reducing DSI from 91 to 60 days (by lowering inventory to ~$33,000) would free approximately $17,000 in working capital.
What is a good DSI value?
A 'good' DSI depends on industry: grocery stores target under 30 days, general retail aims for 45-75 days, manufacturing accepts 90-150 days, and luxury goods may exceed 180 days. The key is whether your DSI matches industry norms and your business strategy.
How is DSI different from Days of Inventory on Hand (DOH)?
DSI uses dollar values (Ending Inventory / COGS x Days) and is a financial metric appearing on balance sheet analysis. DOH uses physical units (Current Units / Daily Unit Demand) and is an operational metric for warehouse planning. Use our Days of Inventory on Hand Calculator for unit-based analysis.