Stock Coverage Calculator
Calculate Stock Coverage step by step: (on hand + on order) ÷ expected daily demand.
In short
Formula: Coverage (days) = (on hand + on order) ÷ expected daily demand.
What this calculator does
Calculate Stock Coverage step by step: (on hand + on order) ÷ expected daily demand. Worked example, questions and limitations included.
Use it to turn Stock on hand, Stock on order (enter 0 if none), Expected daily demand into a checked result you can compare, copy, or rerun with different assumptions.
The page shows the formula, a numeric worked example, and the assumptions that affect this inventory calculation.
Inputs and what they mean
- Stock on hand
- — number value.
- Stock on order (enter 0 if none)
- — number value.
- Expected daily demand
- — number value.
How to use it
- Enter each value in the unit shown next to the box (use the unit converter first if your numbers are in other units).
- Check the breakdown to see every intermediate step.
- Read the limitations before relying on the result.
Formula
Forward-looking days of supply (ASCM dictionary).
On-order stock is shown both included and excluded, because it only helps once it arrives.
Demand is your forecast; no pattern is assumed.
Coverage (days) = (on hand + on order) ÷ expected daily demand.
Inputs used: Stock on hand, Stock on order (enter 0 if none), Expected daily demand.
Worked example
Days of supply
- 1,500 ÷ 50 = 30 days.
- On hand only = 24 days.
Reading the result
The headline figure is the main answer. Any breakdown underneath shows the parts that make it up, so you can check the working and see what changes when you adjust an input.
Limitations and assumptions
- Constant demand assumed.
- Ignores backorders and allocations.
- No arrival timing.
- Results are planning estimates built only from the figures you enter. No prices, rates, demand patterns or service levels are built in, and the results are not supplier quotes or carrier rates.
- The result depends on the values you enter for this stock coverage calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.
Common questions
Why show on-hand only?
If the order arrives late, on-hand coverage is what you really have. Check the formula, example, and limitations on this page before using the result for a real inventory decision.
Can I use weeks?
Yes — use weekly demand and read the result as weeks. Check the formula, example, and limitations on this page before using the result for a real inventory decision.
How does this differ from DIO?
DIO is backward-looking and value-based; coverage looks forward in units. Check the formula, example, and limitations on this page before using the result for a real inventory decision.
How do I use the Stock Coverage Calculator?
Enter the required values for Stock on hand, Stock on order (enter 0 if none), Expected daily demand. The calculator applies the formula on this page and shows the main result with any supporting breakdown so you can check the arithmetic.
What formula does the Stock Coverage Calculator use?
Coverage (days) = (on hand + on order) ÷ expected daily demand. The visible formula section above lists the calculation path and the edge cases the page handles, so the result can be checked without relying on the form alone.
Can the Stock Coverage Calculator be used for exact decisions?
Use it as a calculation aid, not as a substitute for checking the underlying rule, contract, policy, or professional advice that applies to your situation. When a result depends on local rules, personal details, prices, or dates, enter those values yourself and confirm them before acting.
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