Barcode guides
20 guides, grouped by the decision they help with. Each one answers a single question and lists the standards and documentation it relies on. Guides marked “In-depth” are the best place to start.
Barcode numbers and GTINs
A barcode is only a picture of a number. These guides cover where that number comes from: GS1 licensing, GTIN formats, check digits, and when a product change means you need a new number.
- In-depth
How to Get UPC Barcodes for Your Products, Step by Step
How U.S. sellers get UPC barcodes: when you need a GS1 number, single GTIN vs. company prefix, assigning numbers, making the image, avoiding resold codes.
Updated October 1, 2026 · 11 min read
How Check Digits Work: GS1 Mod-10 Worked Examples
Step-by-step GS1 check digit math on a UPC-A and an EAN-13, why it catches typos and most swapped digits, and the errors it can't catch.
Updated October 1, 2026 · 5 min read
SKU vs UPC vs ASIN vs FNSKU: What Each Number Is For
SKU, UPC, ASIN and FNSKU compared: who issues each code, what it identifies, where it is used, and which one belongs on your product or FBA label.
Updated October 1, 2026 · 5 min read
What Is a GTIN? GTIN-8, GTIN-12, GTIN-13 and GTIN-14 Explained
A GTIN is the product number inside a retail barcode. Learn the four GTIN lengths, how they relate, why leading zeros matter, and GTIN vs. barcode.
Updated October 1, 2026 · 5 min read
When Do You Need a New GTIN? The GS1 Rules in Plain English
The GS1 GTIN Management Standard sets ten rules for when a product change needs a new GTIN. Here is each rule, plus the changes that do not need one.
Updated October 1, 2026 · 6 min read
Choosing a barcode type
UPC, EAN, Code 128, Code 39, ITF-14 and GS1-128 each exist for a job. Start with the decision guide, then read the comparison that matches the choice in front of you.
- In-depth
Which Barcode Type Do I Need? A Decision Guide by Job
Match each labeling job to the right barcode: UPC or EAN for retail, ITF-14 or GS1-128 for cartons, Code 128 for bins and assets, QR for links.
Updated October 1, 2026 · 11 min read
Code 128 Explained: Code Sets, Check Character and GS1-128
How Code 128 works: code sets A, B and C, start and stop characters, the mod-103 check character, and how GS1-128 adds FNC1 and Application Identifiers.
Updated October 1, 2026 · 6 min read
Code 39 vs. Code 128: Which to Use for Internal Labels
Code 39 vs. Code 128 for bin, shelf and asset labels: character sets, label width, check characters, scanner settings, and when Code 39 still makes sense.
Updated October 1, 2026 · 5 min read
ITF-14 Barcodes for Shipping Cartons: When and How to Use Them
When an outer carton needs an ITF-14, how to build a GTIN-14 with the indicator digit, bearer bar and size rules, and when a GS1-128 label fits better.
Updated October 1, 2026 · 6 min read
UPC vs. EAN: What's the Difference and Which to Use?
UPC-A and EAN-13 are one barcode family with 12 vs. 13 digits. See how they convert with a leading zero, U.S. acceptance, and when UPC-E or EAN-8 fit.
Updated October 1, 2026 · 5 min read
Printing and scanning
Most barcodes that fail do so because of size, quiet zone, contrast or printing, not because the generator was wrong. These guides cover print settings, label stock, scanners and troubleshooting.
- In-depth
How to Print Barcodes That Scan: Size, Quiet Zones, Color
Print UPC, EAN, Code 128 and ITF-14 barcodes that scan: X-dimension, quiet zones, colors, printer dots, file export, and how to test before a full run.
Updated October 1, 2026 · 13 min read
Barcode Not Scanning? A Checklist From Most to Least Likely
Barcode won't scan? Check causes in order: scanner type and settings, quiet zones, size, print quality, colors, check digits, and how scans reach software.
Updated October 1, 2026 · 6 min read
Direct Thermal vs Thermal Transfer vs Sheet Labels for Barcodes
Compare direct thermal, thermal transfer, and laser or inkjet sheet labels for barcodes: how each prints, ribbons, label materials, adhesives, durability.
Updated October 1, 2026 · 6 min read
How Barcode Scanners Work: Laser, Imager and Phone Camera
How laser scanners, linear imagers, 2D area imagers and phone cameras read barcodes, how scans reach software, and why 1D scanners can't read QR codes.
Updated October 1, 2026 · 5 min read
Inventory, assets and shipping
Practical setups for stockrooms, equipment tags, spreadsheets and shipping cartons, written for a small team without a dedicated IT department.
- In-depth
How to Set Up a Barcode Inventory System for a Small Business
A step-by-step plan for barcoding a small stockroom: what to track, a SKU scheme, which codes to print, scanners, software and counting routines.
Updated October 1, 2026 · 11 min read
Asset Tags with Barcodes: Numbering, Materials and Placement
How to number barcode asset tags, choose a symbology and label material, place tags so they last, keep the records and retire tags properly.
Updated October 1, 2026 · 5 min read
Barcodes in Excel and Google Sheets: Fonts and Formulas
How barcode fonts work in Excel and Google Sheets, why Code 39 needs asterisks and Code 128 needs an encoder, plus a UPC check-digit formula.
Updated October 1, 2026 · 5 min read
QR codes
When a QR code is the right tool, how big to print it, which error correction level to choose, and why a static QR code does not expire.
Do QR Codes Expire? Static vs. Dynamic, and What Really Breaks
Static QR codes never expire, but the link inside can. Learn how dynamic QR codes work and what really breaks a printed code, from dead URLs to bad print.
Updated October 1, 2026 · 5 min read
QR Code Size and Error Correction: Print Rules That Scan
How to size a printed QR code: modules and versions, the four-module quiet zone, L/M/Q/H error correction, logos, minimum size by distance, and testing.
Updated October 1, 2026 · 6 min read
QR Code vs. Barcode: Which One Does Your Product Need?
QR codes vs. linear barcodes compared on capacity, scanners and use: UPC/EAN for checkout, QR for links, and where GS1 Digital Link fits in.
Updated October 1, 2026 · 5 min read