Excel product list → EAN-13 / UPC-A → batch barcodes → A4 labels

1. Prepare the spreadsheet as identifiers, not ordinary numbers

Keep EAN / UPC values as text when necessary so leading zeros are not lost. Remove hidden spaces and confirm that each row maps to the correct product.

2. Use existing retail identifiers

The barcode tool can calculate or validate the final check digit, but it does not assign official retail product numbers. Use identifiers obtained through the appropriate business / coding process.

3. Paste one identifier per line

The Barcode section already supports multi-line batch generation. Test a small sample first, then generate the larger batch after the data format is confirmed.

4. Choose EAN-13 or UPC-A according to the identifier you already have

Do not convert one numbering system to another merely because a printer or layout looks convenient. The printed symbol should match the identifier required by the real workflow.

5. Verify before A4 printing

• Check the longest and shortest values.
• Scan a sample with the actual scanner.
• Print one test sheet on ordinary paper.
• Confirm margins and scaling before using label stock.

6. Keep the source list and the generated batch together

Retain the original Excel / CSV file and record the generation date so incorrect labels can be traced back to the source data.