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Digital Product Reorder Calculator

The Digital Product Reorder Calculator estimates when a creator or reseller should replenish a limited digital inventory such as license keys, prepaid access codes, externally hosted seats, or vendor-supplied download allocations. It combines average daily demand, supplier lead time, safety stock, and current usable inventory.

Unlike ordinary downloadable files, some digital products have constrained units or credentials that must be purchased or generated in batches. The calculator produces a reorder point, days of stock remaining, and a suggested order quantity to restore a target stock level. It is not needed for products with truly unlimited delivery capacity.

Demand and inventory inputs

units/day
days
units
units
units
Result
—
Reorder point
Expected lead-time demand—
Days of stock remaining—
Reorder status—
Suggested order quantity—

1. Measure average daily demand
Use a representative period and exclude one-time spikes unless they are expected to repeat.

2. Enter replenishment lead time
Count the days from placing an order until new keys or units are usable.

3. Set safety stock
Add a buffer for demand variation, supplier delay, failed codes, or reserved inventory.

4. Enter current and target stock
Current stock should include only usable units; target stock is the desired post-reorder level.

5. Act on the reorder status
Order when current stock reaches or falls below the calculated point.

Lead-time demand = Average daily demand × Lead time | Reorder point = Lead-time demand + Safety stock | Days remaining = Current stock ÷ Average daily demand | Suggested order = max(0, Target stock − Current stock)

Where:

  • Demand is measured in units per day.
  • Lead time is measured in days.
  • Safety, current, and target stock are units.

Assumptions: Demand and lead time are treated as stable averages. The suggested quantity does not include minimum-order rules or expected demand during the next review cycle.

What the result means

The reorder point is the stock level at which replenishment should be initiated under the entered assumptions.

For unlimited self-hosted files, operational capacity rather than inventory is usually the relevant constraint.

Given:
Daily demand 18 units; lead time 7 days; safety stock 40; current stock 130; target stock 300.

Calculation:
Lead-time demand = 18 × 7 = 126 units. Reorder point = 126 + 40 = 166 units. Days remaining = 130 ÷ 18 = 7.2 days. Suggested order = 300 − 130 = 170 units.

Result:
Reorder point 166 units; reorder now; suggested order 170 units.

Interpretation:
Current inventory is already below the buffer-adjusted reorder point and may not cover the full lead time safely.

Why would a digital product have inventory?

Some products depend on purchased license keys, limited seats, serial numbers, prepaid credits, or vendor allocations. A freely duplicable file usually does not require this calculation.

How should safety stock be selected?

Use historical demand variation, supplier reliability, and the cost of running out. Higher uncertainty generally justifies a larger buffer.

Can weekly demand be used?

Convert it to a daily average or express both demand and lead time in matching units. Mixing weekly demand with lead time in days gives an incorrect result.

What if average demand is zero?

The reorder point becomes the safety-stock amount and days remaining is undefined. Review whether the product is inactive before replenishing.

Does the suggested order quantity include future sales during lead time?

It restores current inventory to the chosen target. Set the target high enough to cover the desired cycle, including expected future demand.