Is this calculator specific to Shopify?

The math is ecommerce-specific and works especially well for Shopify stores because it includes the costs Shopify merchants usually need to model: COGS, payment fees, shipping, returns, ad spend, inventory, conversion rate, or repeat purchases depending on the tool.

Should I use gross margin or contribution margin?

Use contribution margin when you are making advertising, discount, or growth decisions. Gross margin is useful, but contribution margin is stricter because it accounts for variable costs like payment fees, fulfillment, shipping, returns, and app costs.

Why does the tool use default values?

Defaults make the calculator useful immediately and show the shape of the result before you enter your own numbers. Replace them with your store's actual numbers before making a final decision.

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Stockout Cost Calculator

Estimate the revenue, gross profit, and repeat-purchase value lost when a product goes out of stock.

Stockout cost calculator

Estimate the real cost of running out of stock, including lost contribution profit and likely repeat-purchase loss.

Daily units sold

Profit per unit

Stockout days

Average order value

Repeat purchase loss

A conservative estimate of future value lost when shoppers cannot buy.

Estimated stockout cost

$10,691

Lost units

288

Lost revenue

$21,888

Lost gross profit

$8,064

Repeat loss

$2,627

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About this tool

What this free tool calculates

Use this when deciding whether to expedite inventory, air freight a replenishment, or accept a stockout.

How to use the result

The calculator multiplies daily unit sales by stockout days, then applies profit per unit, AOV, and an estimated repeat-purchase loss.

If stockout cost is higher than expedited replenishment, the faster shipment is probably worth it. If not, protect cash and communicate clearly.

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Why the calculator stays input-driven

This free ecommerce tool does not guess demand, scrape competitors, or invent benchmarks. Change the numbers to match your store, then use the result to decide whether a product, campaign, discount, or inventory move is worth doing.

Frequently Asked Questions

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