Label Studio CreatorBarcode GS1 Tutorial
A practical guide for creating, validating, and printing GS1-128, GS1 DataMatrix, GS1 QR, EAN, UPC, and SSCC labels.
Purpose
This tutorial explains how to choose the right barcode, encode GS1 Application Identifiers correctly, validate check digits and quiet zones, and avoid unreadable printed codes.
1. Choose the right barcode
| Barcode | Use when | Typical content |
|---|---|---|
| EAN-13 / UPC-A | Retail product identification. | GTIN only, fixed length, checkout scanning. |
| GS1-128 | Logistics, cartons, pallets, variable AI data. | GTIN, batch, expiry, SSCC, quantity. |
| GS1 DataMatrix | Small labels, medical/UDI, high data density. | GTIN, serial, lot, expiry. |
| GS1 QR | Consumer-facing traceability and web links. | Digital Link, product URL, lot data. |
| PDF417 / Aztec | Special logistics or transport workflows. | Large encoded payloads. |
2. Understand GS1 Application Identifiers
GS1 AIs tell scanners what each value means. Use the Barcode Assistant for presets and validation.
(01)GTIN, 14 digits(10)Batch or lot, variable length(17)Expiry date, YYMMDD(21)Serial number, variable length(00)SSCC, 18 digits(310x)Net weight in kg with decimal precision
3. Use Barcode Assistant
Select preset
Choose retail, logistics SSCC, food batch/expiry, medical UDI, or traceability QR.
Enter fields
Use fixed data or variable fields from CSV, Excel, SQL, REST, or e-commerce orders.
Preview
Check rendered barcode, HRI text, size, and quiet zones before insertion.
Insert
Insert into the label template and keep it inside the safe area.
4. Validate before production
| Validation | What to check |
|---|---|
| Check digit | GTIN/EAN/UPC/SSCC check digits must be valid. |
| AI syntax | Fixed and variable-length AIs must be encoded correctly. |
| Quiet zone | Keep clear space around the barcode; do not place text or cut lines too close. |
| Size and X-dimension | Do not scale below scanner tolerance. |
| Contrast | Printed code must scan on the real substrate. |
| HRI | Human-readable text must match encoded data. |
5. Quiet zones and cut safety
6. Print test checklist
Print small sample
Print 3 to 10 labels or one sheet before batch production.
Scan with target devices
Use handheld scanner, phone, or production scanner depending on use case.
Check substrate
Dark, transparent, kraft, or glossy media may need white support or higher contrast.
Log result
Keep validation status in production history before release.