Catalog identity checks

Duplicate SKU and Barcode Finder

Supplier imports and copy-paste edits quietly create variants that share a SKU or barcode. Scan a product export locally and see every duplicate grouped with its products before it breaks inventory or feeds.

Local browser scanSafe fixes onlyShopify-focused checks

Browser-side scan

Drop a product CSV to scan for duplicates

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No CSV selected

No CSV selectedUpload a product or inventory export to find duplicate SKUs, duplicate barcodes, and repeated variant rows. Files are read locally and nothing is uploaded.
Private by default. Your Shopify product CSV data stays in this browser session. The export applies only safe deterministic changes and leaves manual-review items in the findings list.

Use this duplicate SKU finder when Shopify inventory counts look wrong, Merchant Center rejects variants for shared GTINs, or a supplier CSV import created repeated rows. Upload a product or inventory export carrying Variant SKU and Variant Barcode columns; the checker groups every repeated SKU and barcode, separates duplicates inside one product from SKUs reused across different products, and counts rows with blank SKUs that cannot be tracked at all. The export is a worksheet listing each affected row with its handle, options, and a review note — the tool reports duplicates, it does not decide which row to keep, and nothing leaves your browser.

Import blockers

Common causes this scan checks

  • A supplier CSV was imported twice or with overlapping batches, duplicating variant rows.
  • Products were duplicated in admin to save time and kept the original SKUs and barcodes.
  • Spreadsheet autofill dragged one SKU or GTIN down an entire column.
  • Bundles and standalone products intentionally share a SKU, which some channels reject.

Workflow

How to use the cleaned CSV

  1. Export products or inventory from Shopify and upload the CSV here.
  2. Review SKUs reused across different products first — these break inventory tracking and feeds.
  3. Decide per group which row keeps the identifier and which rows get new SKUs or barcodes.
  4. Export the duplicates worksheet, correct the values, and re-import or bulk-edit in admin.

Auto-fix policy

What the export can safely change

  • Detects SKU and barcode columns from product and inventory exports, including GTIN, EAN, and UPC aliases.
  • Groups duplicate values case-insensitively and separates same-product repeats from cross-product reuse.
  • Counts blank SKU rows that the duplicate check cannot cover.
  • Exports a grouped worksheet with handle, options, and review notes instead of deleting any row.

CSV example

CSV example: duplicate SKU and barcode groups

The finder sees MUG-1 reused by two different products and groups both rows in the worksheet, so the merchant decides which mug keeps the SKU instead of discovering the clash in inventory reports.

Before
Handle,Title,Variant SKU,Variant Barcode
blue-mug,Blue Mug,MUG-1,4006381333931
travel-mug,Travel Mug,MUG-1,4006381333948
After
Issue type,Duplicate value,Handle,Variant SKU,Barcode,Title,Options,Review note,Source row
Duplicate SKU,MUG-1,blue-mug,MUG-1,4006381333931,Blue Mug,,Same SKU on 2 variants across 2 products; keep one or make SKUs unique,2
Duplicate SKU,MUG-1,travel-mug,MUG-1,4006381333948,Travel Mug,,Same SKU on 2 variants across 2 products; keep one or make SKUs unique,3

FAQ

Shopify CSV questions

Does Shopify itself stop duplicate SKUs?

No. Shopify allows the same SKU on any number of variants, so duplicates only surface later as inventory confusion, reporting noise, or feed disapprovals.

Are duplicate barcodes worse than duplicate SKUs?

They cause different problems. Duplicate barcodes break GTIN-based channels like Google Merchant Center and POS scanning, while duplicate SKUs corrupt inventory tracking and analytics.

Will the tool delete the duplicate rows for me?

No. Which row keeps the identifier is a merchant decision. The worksheet groups the affected rows so you can fix them in a spreadsheet or Shopify bulk editor.

Is my product CSV uploaded to a server?

No. The file is read locally in your browser with the File API and nothing is stored or transmitted.

Related tools

Feedback

How is this tool working for you?

Found a bug, a false alarm, or a missing check? Tell me — a human reads every note.