Free QR Code & Barcode Generator

The Professional Guide to QR Code & Barcode Printing

NO QR CODE produces compliant barcodes and QR codes according to international ISO standards. Following optical printing best practices guarantees 100% first-pass read rates across laser scanners and smartphone cameras.

1. Sizing Guidelines & Scan Distances

For QR codes, adhere to the 10:1 distance-to-size rule (Width = Distance ÷ 10). For 1D barcodes, bar width (X-dimension) must never drop below 0.25 mm (10 mils) on printed labels to prevent scanner bar-merge errors.

• Retail Product Packaging: EAN-13 / UPC-A nominal size is 37.29 mm × 25.93 mm.
• Business Cards & Menus: Minimum QR code size 2.0 cm × 2.0 cm (0.8 × 0.8 in).
• Logistics Shipping Cartons: Code 128 minimum height 32 mm with 0.5 mm bar width.

2. Optical Contrast & Color Selection

Optical barcode scanners illuminate codes with red lasers (630–670 nm). Therefore, red, orange, or yellow bars will appear white and fail to scan! Always use high-contrast combinations: black or dark blue bars on a crisp white or light background.

3. Quiet Zones (Margins) Are Mandatory

Every 1D barcode requires a clear quiet zone on both the left and right sides (minimum 10 times the narrow bar width). For QR codes, maintain at least 4 modules of uninterrupted margin around the entire boundary.