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What is this stockout costing you?

A product goes out of stock and the lost sales are invisible. Put your numbers in and watch the real cost add up, live.

In one line

A stockout costs you units sold per day × price × days out of stock. This calculator runs that math live and projects the total until your restock lands.

Your numbers

#
$
days
days

Lost revenue meter

Lost so far
$0
Lost per day$0
Units not sold so far0
Projected loss by restock$0

Stop it happening again

EZstock tracks how fast each product sells and warns you before it runs out, so you reorder in time. Free plan, no card needed.

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How the math works

The direct cost of a stockout is the revenue you would have earned if the product had stayed in stock. It comes down to how fast it sells and for how long it is gone.

Lost revenue = units sold per day × price per unit × days out of stock
01 / SALES RATE

Units per day

How many you sold on an average day before the shelf went empty. Your recent daily average is the honest number to use.

02 / VALUE

Price per unit

The selling price of one unit. Use the price the customer pays, not your cost.

03 / DURATION

Days out of stock

Every day out multiplies the loss. A slow reorder turns a small gap into a large number.

What a stockout also costs

The meter above measures direct lost revenue, the part you can put a number on. A stockout usually costs more than that:

↗ SWITCHING

Customers leave

A shopper who wanted it now buys from a competitor and may not come back.

↺ REPEAT

Lost repeat orders

A first purchase that never happens is also every reorder that would have followed it.

▽ RANKING

Search & ad drop

A sold-out product can lose search placement and waste ad spend sending traffic to an unavailable page.

Questions

How do you calculate the cost of a stockout?+

Multiply average units sold per day by the price per unit to get lost revenue per day, then multiply by the days out of stock. This tool runs that live and projects the total to your restock date.

Is this calculator free?+

Yes. No signup, no limits. It runs entirely in your browser and nothing you type is uploaded or stored.

What number should I use for units per day?+

Use the product's recent average daily sales from before it went out of stock. If sales vary a lot, use the average over a normal 30-day stretch.

How do I stop stockouts from happening?+

Set a reorder point for each product and watch days of stock left based on how fast it sells. EZstock tracks sales velocity and warns you before a product runs out, so you reorder in time. You can bring your Stocky data over too.

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