Find and fix duplicate barcodes in Shopify

LabelCraft - barcode labels for Shopify that print at exactly the size you set.

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The guarantees behind every label

Exact to ±0.1 mm

Every label prints at the size you set - measured, not approximate.

Never a silent failure

Overflow or a missing barcode always raises a visible warning before you print.

Whole-dot barcodes

Modules snap to your printer's dots, so codes stay crisp and scan first time.

Your barcodes, untouched

We never overwrite or reassign a product's existing barcode.

Two products that share one barcode are a silent catalog bug. Shopify lets you save the duplicate with no warning, but at the till a scan can ring up the wrong product, and your stock counts quietly drift apart. LabelCraft's Barcode Audit finds every shared code across your whole catalog, before a bad label is ever printed.

Why a shared barcode is always wrong

GS1 assigns one GTIN per distinct trade item. So any code carried by two sellable variants - a real retail GTIN or a custom Code 128 value alike - is wrong by definition. A scanner cannot know which of the two products you meant, so checkout, returns and inventory all become a guess.

Why you cannot catch them one product at a time

Inspecting a single barcode tells you whether that code is a valid, scannable GTIN: its check digit, its length, its prefix. It can never tell you the same code is also sitting on another product, because a collision is only visible across the whole catalog. You need a catalog-wide pass, not a row-by-row check.

What counts as a duplicate, and what does not

LabelCraft is deliberately conservative. It trims the spaces around a value, then compares what is left exactly - so it only ever flags a collision it is sure about, and never invents a false one or hides a real difference:

12345 with stray spaces around it and 12345 are a duplicate - only the surrounding spaces differ, and those are trimmed first.
0012345 and 12345 are not a duplicate - a leading zero changes the symbol a scanner reads.
ABC123 and abc123 are not a duplicate - Code 128 is case-sensitive.
A blank barcode counts as missing, never a duplicate - empty values are skipped, not flagged.

How LabelCraft finds and fixes duplicates

Barcode Audit reads your live catalog in pages of 50 variants, up to 200 pages, then groups every colliding variant worst-first - the code shared by the most products sits at the top. It lists up to 200 collision groups with up to 50 variants in each, and always reports the true total when there are more, so nothing is silently capped.

Open Barcode Audit in LabelCraft - it scans your catalog automatically, no setup.
For each group, choose the one variant that keeps the code.
LabelCraft re-codes the rest, so the keeper keeps its barcode and the collision is resolved.
Reprint the corrected labels so the shelf matches the catalog again.

Stop duplicates getting in

Duplicates almost always arrive in a bulk edit - a spreadsheet row copied down, or a supplier file that reuses one code across a range. Generate a unique barcode for each new variant instead of reusing one, and run the audit after every large import. See the free barcode generator and adding barcodes in bulk.

Install free - 200 labels per month →

More guides: GTIN check digits, fix an invalid barcode digit, SKU vs barcode - or contact LabelCraft support.