Walmart Marketplace UPC check

Client

Walmart Marketplace UPC check for sellers on Walmart.com. Paste UPC/EAN/GTIN for local mod-10 before item creation—does not query Walmart Item Setup or attribute matching.

Before Walmart item setup

Walmart requires valid GTIN for most categories. Run mod-10 here, then paste same digits into Item Spec or feed—invalid check digit causes immediate setup failure.

Privacy: every comparison runs locally in your tab. Toolcore performs no GS1 registry lookup, product database match, or price scan—checksum math only.
?

GTIN‑8, UPC‑A (GTIN‑12), EAN‑13, and logistic GTIN‑14 all end with the same ISO/IEC GS1 modulus‑10 weight‑3 algorithm used by the barcode generator when it pads shortened bodies with a check digit. Alternate lengths map to retailer packaging standards (coupon GTIN‑12, carton GTIN‑14, compact GTIN‑8).

Result

Passes modulus‑10 GS1 rule for GTIN-13 (13 digits).

Common use cases

  • Validate UPC on multi-channel feed before Walmart column split.
  • Catch typos before Walmart OAuth catalog upload.
  • Agency QA on client Walmart onboarding spreadsheets.

Common mistakes to avoid

  • Valid UPC but Walmart item exists under different brand

    Catalog conflict is separate from checksum validation.

FAQ

Does Walmart UPC check call Seller Center?

No—local GS1 mod-10 only.

Common search terms

Phrases people search for that match this tool. See the full long-tail keyword index.

  • gtin checksum verifier online
  • ean 13 check digit validate browser
  • upc-a modulus 10 checker locally
  • gtin 14 logistic barcode checksum
  • gs1 digit string validator no lookup

More tools

Related utilities you can open in another tab—mostly client-side.