100% Client-Side In-Browser Calculation — Zero Server Uploads
What is a UPC-A Barcode and How is the Check Digit Calculated?
A UPC-A barcode is a 12-digit numeric retail symbology used across North America and Amazon FBA. Enter your 11-digit GTIN prefix and item reference; our generator automatically computes the 12th Modulo-10 check digit and exports crisp 300 DPI SVG or PNG vectors.
Symbology Property
UPC-A Specification
Retail / E-Commerce Use Case
Digits Encoded
Exact 12 numeric digits (0–9)
POS Scanning & North America Retail
Check Digit
Modulo-10 (Weights: Odd × 3, Even × 1)
Error detection at laser barcode scanners
Print Density
100% nominal magnification (1.469" x 1.02")
Thermal direct and laser packaging printing
Symbology Technical Specifications
This barcode generator operates strictly compliant with the GS1 UPC-A / ANSI X3.182 specification standard.
All vector geometry is calculated locally in your browser memory. No proprietary tracking numbers, internal SKUs, or customer records are ever transmitted across the network.
Barcode Symbology Questions
Yes, UPC-A is the primary retail identifier required for brand listings across Amazon US and North American retailers.