Inventory Forecast Calculator
Calculate projected ending stock: opening stock + scheduled receipts − forecast demand.
In short
Formula: Projected ending stock = opening stock + scheduled receipts − forecast demand.
What this calculator does
Calculate projected ending stock: opening stock + scheduled receipts − forecast demand. Worked example, questions and limitations included.
Use it to turn Opening stock, Scheduled receipts in the period, Forecast demand in the period, Safety stock target (enter 0 if none) 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 supply chain calculation.
Inputs and what they mean
- Opening stock
- — number value.
- Scheduled receipts in the period
- — number value.
- Forecast demand in the period
- — number value.
- Safety stock target (enter 0 if none)
- — 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
Projected available balance as used in MRP (ASCM dictionary).
Forecast demand is yours — from the demand forecast calculator or your plan.
Run period by period for a multi-period projection.
Projected ending stock = opening stock + scheduled receipts − forecast demand.
Inputs used: Opening stock, Scheduled receipts in the period, Forecast demand in the period, Safety stock target (enter 0 if none).
Worked example
Next month
- 800 + 500 − 900 = 400 units.
- 150 above safety stock.
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
- One period.
- No timing within the period.
- Forecast accuracy not measured.
- 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 inventory forecast calculator; it does not supply missing rates, rules, prices, dates, or assumptions for you.
Common questions
What if receipts arrive late in the period?
You could run short mid-period even if the end looks fine. Split the period.
Should backorders be subtracted?
Yes — add them to demand. Check the formula, example, and limitations on this page before using the result for a real supply chain decision.
Where does safety stock come from?
The safety stock calculator. Check the formula, example, and limitations on this page before using the result for a real supply chain decision.
How do I use the Inventory Forecast Calculator?
Enter the required values for Opening stock, Scheduled receipts in the period, Forecast demand in the period, Safety stock target (enter 0 if none). 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 Inventory Forecast Calculator use?
Projected ending stock = opening stock + scheduled receipts − forecast 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 Inventory Forecast 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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