Dead stock checker: how much of your Shopify stock has stopped selling?

How the checker decides

Every variant with stock goes into exactly one group, from the date of its last sale in your orders. The groups and their names are the ones Mufatech Clearance uses for "How old is your stock", and the money in them adds up to the money in stock to the cent.

Thresholds are Store Diagnosis's defaults. "Not selling" in the report is the four orange groups at the top; "stuck" adds slow stock.

• Cash tied up is units on hand × cost per item. Where cost per item is empty, the checker assumes a 50% margin, marks the row "cost estimated" and says how many it guessed.
• The dead stock score is 100 − 100 × (never sold + 180 days or more + half of 90–179 days + a quarter of slow) ÷ all stock at cost. 100 means no money is stuck.
• The markdown is rounded down to a 5% step and never prices a unit under its floor, cost plus 5%. If the floor leaves less than 5% of room, it suggests a bundle with a steady seller, or clearing the stock another way, instead of a discount.
• Days of stock is units on hand ÷ the daily pace of the last 90 days, counted over the days the variant could actually sell. "No sale in 90 days" means there is no pace to divide by.

For the same products, stock and orders, the figures are the ones Store Diagnosis shows: the checker is its dead-stock engine, bundled for the browser, and the page's tests run both on Diagnosis's demo store and compare every variant to the cent. One difference is the file format's: a product export has no "date added", so a variant with no sale at all is listed as never sold even if you added it last week. Store Diagnosis reads that date from your store and leaves stock under 30 days old alone.

How to export the files from Shopify

You need to be the store owner or a staff member who can export products and orders. Large exports are emailed to you rather than downloaded, so keep your inbox open.¹³

1. Products export. In your Shopify admin go to Products and click Export. Choose All products and CSV file for Excel, Numbers, or another spreadsheet program, then Export products. For all products Shopify emails the file to you.¹ The checker reads the handle, title, SKU, options, price, Cost per item, Inventory quantity and status. Fill in cost per item first if you can: it is "how much it costs you to make or acquire the product or variant", and without it every figure is an estimate.²
2. Orders export. Go to Orders, click Export, choose All orders (or Orders by date covering at least the last 13 months), pick the CSV format and click Export orders, not "Export transaction histories". More than 50 orders are emailed to you; a very large store can wait an hour or more.³ The checker reads the order number, date, status, currency and each line item's quantity, name, price and SKU. The export also holds your customers' emails, names, addresses and phone numbers;³ the checker skips those columns as it reads.
3. Inventory export (optional). The products file's inventory quantity is meant for stores with one location.² With more than one, go to Products › Inventory, click Export, choose All locations, All states, All variants and the CSV format, then Export inventory.⁴ The checker adds up On hand across locations, which is what Store Diagnosis counts; with the "Available" layout it adds up the location columns.
4. Drop the files above. All at once is fine: the checker reads each file's header to tell which is which. A 50 MB orders file takes a few seconds; the page stays usable while it reads.

Why nothing is uploaded, and how you can check

An orders export is a list of your customers. It should not go to a website to answer a question about stock, so the checker is built so that it cannot:

• The files are read in this tab. The checker hands them to a Web Worker, a background script of this page, which reads each file in 1 MB pieces straight from your disk. Only the summary you see comes back to the page.
• Customer columns are never kept. In the orders file the reader keeps nine columns: order number, date, cancelled date, financial status, currency, and the line item's quantity, name, price and SKU. Every other cell, including email, billing and shipping names and addresses, phone numbers and notes, is skipped as it is parsed and never stored. The report lists the columns it skipped.
• The page is not allowed to send your data anywhere. Its Content Security Policy permits connections to one address only, Cloudflare's cookieless page-view counter, and our code never calls it; the worker that reads your files is served with a policy that permits no connections at all.⁶ Browsers enforce these rules themselves.
• The download is made here. The results CSV is built in memory and saved by your browser.

To check for yourself, open your browser's developer tools on the Network tab, then drop your files. The only new request is the checker's own code, engine.js, fetched once, and nothing is sent after it. Its source, and the page's app.js, contain no network call at all. Close the tab and the data is gone.

Do it by hand in a spreadsheet

The checker saves the work, but the method is simple enough to do yourself with the same two exports:

1. In the products export, keep the rows with stock above zero and add a column for cash tied up = inventory quantity × cost per item.
2. In the orders export, leave out cancelled orders, then find the latest Created at for each Lineitem SKU. A pivot table with SKU as rows and the maximum of Created at as the value does it.
3. Look up each product row's SKU in that pivot and add days since last sale = today − last sale. No match means it never sold in the file.
4. Group the rows into 90–179 days, 180–364 days, a year or more and never sold, total the cash in each, and sort the whole list by cash tied up, largest first.
5. For each row at the top, the floor is cost × 1.05, and the deepest markdown it allows is 1 − floor ÷ price. Start at 25% for 90–179 days and 40% for 180 days or more, never deeper than the floor allows. The markdown calculator adds card fees, shipping, returns and VAT to the floor.

The dead stock guide covers the Shopify reports that help, the formulas and the pitfalls, such as variants without a SKU, which order exports cannot match.

Every night, automatically: Store Diagnosis

Exports go out of date the day after you make them. Store Diagnosis is our free, read-only Shopify app, live on the Shopify App Store. It runs this same dead-stock engine on your store every night, from live stock, cost and every order, with each product's real date added, so new stock is never called dead. Each finding shows the arithmetic, the markdown and the steps to do it in your admin. It never changes a price.

Mark it down safely: Mufatech Clearance

Mufatech Clearance is the app that changes the prices. It takes the stuck stock this checker finds, marks it down step by step as it ages, previews every change, blocks any price under your floor, and puts back exactly the prices it changed when a sale ends. It is coming to the Shopify App Store and cannot be installed yet. When it is listed it will have a Free plan for up to 3 campaigns and 200 variants, Pro at $3.99 a month, and Plus at $7.99 a month.

Frequently asked questions