Schedule Coverage Calculator
How to Use This Tool
Enter your current inventory count, average daily sales volume, and optionally the number of days in your upcoming sales schedule. Click Calculate to see how many days your stock will last and whether your schedule is fully covered. The optional schedule field helps you plan for specific promotions or bulk orders.
Formula and Logic
Days of Coverage = Available Units ÷ Average Daily Sales
Schedule Coverage Ratio = (Available Units ÷ (Average Daily Sales × Schedule Days)) × 100%
If the coverage ratio is 100% or higher, the schedule is fully covered. If below 100%, the shortfall equals (Total Schedule Demand - Available Units).
Practical Notes
For e-commerce sellers, maintain at least 30-60 days of coverage for fast-moving products to account for shipping delays and demand spikes. In trade businesses, factor in supplier lead times: if your supplier takes 14 days, you need at least 14 days of coverage plus a safety buffer. Monitor your gross margin threshold—if coverage drops below 20 days, prioritize restocking to avoid lost sales and maintain profitability. Seasonal businesses should adjust daily sales inputs to reflect peak periods.
Why This Tool Is Useful
Stockouts directly impact revenue and customer trust. This calculator provides an instant, data-driven view of inventory health, helping you optimize order quantities, negotiate better payment terms with suppliers, and align purchasing with cash flow cycles. It's especially valuable for businesses with limited storage capacity or tight margins.
Frequently Asked Questions
What if my daily sales are highly variable?
Use a 30-day moving average for the most accurate daily demand estimate. For new products without sales history, rely on market benchmarks or pilot test data. Consider using the lower bound of your sales range for conservative planning.
How does lead time affect my target coverage?
Lead time (time from placing an order to receiving it) should be added to your desired coverage buffer. If your supplier takes 21 days and you want a 10-day safety stock, target at least 31 days of coverage. This prevents stockouts during replenishment cycles.
Should I include pending orders in available units?
No. Only include stock physically on hand. Pending purchase orders should be factored into future coverage calculations once received. This avoids double-counting and gives a realistic view of current sellable inventory.
Additional Guidance
Regularly update your daily sales figures to reflect trends and seasonality. Combine this tool with sales forecasting for a comprehensive inventory strategy. For businesses with multiple SKUs, calculate coverage for each product individually and prioritize restocking items with the lowest coverage. Consider setting automated alerts when coverage drops below category-specific thresholds (e.g., 45 days for electronics, 90 days for slow-moving goods).