Find duplicate SKUs in a CSV before an import
Duplicate SKU values can make reconciliation difficult across suppliers, variants and warehouse systems. This checker shows exactly which non-empty identifiers repeat and their CSV line numbers, so you can decide whether each duplicate is intentional. It does not delete, rename, or merge any product data.
How the duplicate check works
- Export a product, variant or supplier CSV containing an SKU or other item-ID column.
- Upload the file above, or test a sample with deliberately repeated IDs.
- Select the SKU/identifier column if it is not detected automatically.
- Review duplicate groups, occurrence counts and original line numbers.
- Download the duplicate report and compare findings with your source catalog.
Example of duplicate SKUs
| CSV line | Title | SKU | Finding |
|---|---|---|---|
| 2 | Blue Tee | TEE-001 | Repeated |
| 3 | Red Tee | TEE-001 | Repeated |
| 4 | Canvas Tote | BAG-002 | Unique |
In this example, TEE-001 appears twice. That signals a review opportunity, not permission to generate new identifiers automatically. The tool matches trimmed non-empty identifiers exactly; case variants such as tee-001 and TEE-001 may need a separate naming-policy review.
Are duplicate SKUs always an error in Shopify?
No. SKU reuse is a business-data quality concern, not automatically a parsing error. Shopify groups product variants by product handle and option values, which is different from SKU uniqueness. Distinguish a repeated SKU from duplicated variant combinations. Our Shopify variant CSV guide explains why.
Can it remove duplicate products?
No. It reports duplicate codes without modifying your catalog. Never remove rows merely because two products share an identifier; they may represent valid listings in different workflows or supplier systems. If the issue is importing a product CSV, also use the Shopify product CSV checker.
The tool runs locally in your browser with a 10 MB / 25,000-row limit. Consult Shopify's product CSV documentation when preparing data for Shopify imports.