Shopify guide · Catalog Health
How to find duplicate SKUs in Shopify
Updated
Short answer
Shopify doesn't stop two variants from sharing a SKU and has no report that lists duplicates. Export your products and count each Variant SKU in a spreadsheet, or use a catalog checker such as Toolbench's Catalog Health, which keeps a live list of every SKU used on more than one variant.
How to do it with Toolbench
Toolbench's Catalog Health scans your whole catalog and lists every SKU used on more than one variant, with the products that share it. The list updates as products are edited, so fixed duplicates drop off.
- Install Toolbench from the Shopify App Store, open Catalog Health and click Turn on.
- Catalog Health scans your catalog. On a large store this takes a few minutes.
- Filter the results to Duplicate SKU to see each shared SKU and the products using it.
- Fix each one in the Shopify admin. The issue clears from the list once the SKU is unique.
Other gaps Catalog Health flags
- Variants with no SKU or no barcode.
- A compare-at price at or below the actual price, which shows a fake discount.
- Missing images, image alt text, SEO title or SEO description.
- No product category, product type, vendor, tags or cost per item.
- No description, or one shorter than a length you set.
Why this happens
Inventory sync apps, ERPs, marketplaces, 3PLs and barcode scanners usually match products by SKU. When two variants share one, stock updates land on the wrong variant, the wrong item gets picked and reports merge two products into one.
Duplicates usually come from duplicating a product and forgetting to change the SKUs, from supplier imports, or from merging catalogs.
Your options in Shopify
Admin search
Searching products for a SKU shows every match, but only once you already know which SKU to look for.
CSV export and a spreadsheet
Export all products from the Products page, open the file and add a count of each value in the Variant SKU column, for example =COUNTIF(column, cell). Filter for counts above 1. Ignore blank SKUs, which count as duplicates of each other.
You only approve what Catalog Health needs
Toolbench asks for no permissions when you install it. When you turn on Catalog Health, Shopify asks you to approve only what this tool uses: read products and inventory.
It doesn't ask for orders, customers, discounts or checkout settings. Each of Toolbench's other tools asks for its own access separately, and only if you turn that tool on, so you never grant access for tools you don't use. Read access means Toolbench can see that data but can't change it.
Before you turn it on
- Catalog Health only reads your products. Fix the SKUs in the Shopify admin or a bulk editor.
- It checks SKUs within one store, not across several stores.
Pricing
Catalog Health is a free tool. The free plan runs any 3 of Toolbench's 12 free tools at a time, with no time limit and no credit card. Premium is $9.99 a month for all 16 tools at once and starts with a 14-day free trial.
Questions
Does Shopify allow duplicate SKUs?
Yes. Shopify doesn't require SKUs to be unique, so two variants can share one without any warning.
Why do duplicate SKUs cause problems?
Apps and systems that match products by SKU, such as inventory syncs, ERPs, marketplaces and 3PLs, can update or pick the wrong variant.
How do I find variants with no SKU in Shopify?
Filter your product CSV export for blank Variant SKU cells, or use Catalog Health, which flags variants with no SKU.
What permissions does Catalog Health need?
Only the ones it uses: read products and inventory. It doesn't ask for orders, customers, discounts or checkout settings. Toolbench asks for no permissions at install, and each of its other tools asks for its own access separately, only if you turn that tool on.