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Inventory Runway Calculator

Estimate current stock coverage, projected units at inbound arrival and any modeled shortage before replenishment.

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Stock coverage

Inventory Runway Calculator

Estimate sellable stock coverage and test whether an entered inbound shipment arrives before modeled stockout.

Current sellable runway

24.6 days

860 units available after reserved and damaged units.

Sellable now

860 units

At inbound arrival

230.0 units

Pre-inbound shortage

0 units

Runway with inbound

41.7 days

The tool assumes a constant daily sales rate and an on-time inbound arrival. Promotions, seasonality, receiving delays and channel reservations can materially change runway.

About the Inventory Runway Calculator

Inventory Runway Calculator removes reserved and damaged units from on-hand inventory before dividing sellable stock by the entered average daily sales rate.

Add an inbound quantity and expected arrival day to see projected inventory immediately before receipt, any pre-arrival shortage and total modeled runway including the shipment.

The model uses constant daily sales and an on-time receipt. It does not forecast promotions, seasonality, channel allocation changes or receiving delays.

Key features

  • Sellable-stock adjustment
  • Current days of inventory
  • Inbound arrival projection
  • Pre-inbound stockout warning
  • Modeled shortage quantity
  • Total runway with inbound
  • Local TXT export

How to use

  1. 1Enter physical on-hand, reserved and damaged units.
  2. 2Enter a representative average daily sales rate.
  3. 3Add inbound quantity and expected arrival days.
  4. 4Review whether stock reaches zero before receipt.
  5. 5Recalculate with downside demand and supplier-delay scenarios.

Examples

Inbound timing check
Input: 950 on hand, reservations, damage, 35 daily sales and 600 units arriving in 18 days
Output: Current runway, arrival stock and post-inbound runway

Frequently asked questions

How is sellable stock calculated?
On-hand units minus reserved units minus damaged units, with a floor of zero.
What happens when daily sales are zero?
Runway is shown as unavailable because division by zero has no useful planning meaning.
Does inbound runway include receiving time?
Only if you include receiving time in the entered inbound-arrival days.
Is this a demand forecast?
No. The entered daily sales rate remains constant throughout the scenario.

Continue your workflow

Open a related tool to prepare your files or refine the finished result.