software lab

What the reports read

last updated: 2026-09-26

The two reports, the data behind them, the period they cover and what they leave out.

Reports has two reports. Both answer questions Shopify's own reports can't, because they rely on the stock history and sales rate this app keeps.

Stockout cost

What running out of stock cost you: for each product that was out of stock, the sales you likely missed, in units, revenue and margin. Read How stockout cost is worked out.

Margin on best sellers

Your class A products — the ones bringing in 80% of your revenue — and how much each one actually earns after its cost. It highlights best sellers that earn little. Read Margin on best sellers.

What they read

  • Sales — your Shopify orders, net of discounts and refunds. Each sale counts on the day it was processed, in your shop's time zone.
  • Costs — the Cost per item of each product in Shopify. You can also set it from the product's page in this app, which writes it to Shopify.
  • Stock history — which days each product had stock. From the day you installed, it is recorded from Shopify as it changes. Before that, Shopify keeps no history, so out-of-stock days are deduced from long gaps in sales.

The period

Both reports cover the last 365 days, the same year used for the A, B and C classes, so the reports and the rest of the app never disagree. The dates are written under each report's summary.

What is left out

  • Products you ignored, in both reports.
  • In the stockout report, products whose stock Shopify does not track, and products that sell on backorder: for neither can we tell when it was really empty.
  • In the margin report, products without a cost: an unknown cost is not a zero margin.

Exporting

Each report has Export CSV, with the same rows as the screen, to open in a spreadsheet.

When they update

Reports are worked out when you open them, from the sales and stock history the app already holds. Sales arrive as orders come in; the Reports page shows when stock levels were last read.