How to Create QR Codes That Scan Well: Size, Contrast, and Common Errors
QR codes are everywhere, but many fail to scan properly due to simple mistakes. This guide explains the technical aspects of QR codes and how to create ones that work reliably in any situation.
How QR Codes Work
QR (Quick Response) codes store data in a two-dimensional pattern of black and white squares. Scanners read these patterns using camera contrast detection, decoding the information embedded in the arrangement of modules.
Unlike barcodes that store data in one dimension, QR codes use both horizontal and vertical axes, allowing them to hold significantly more information in a smaller space.
Getting the Size Right
The minimum scannable size depends on scanning distance and the complexity of the encoded data. As a general rule:
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The more data encoded, the denser the QR code becomes, requiring larger sizes for reliable scanning.
Contrast Is Critical
QR scanners rely on high contrast between the dark and light elements. Poor contrast is the most common cause of scanning failures.
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Understanding Error Correction
QR codes include built-in error correction that allows them to be read even when partially damaged or obscured.
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Higher error correction means a denser code. Choose the level based on your use case and potential for damage.
Common Mistakes to Avoid
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QR Code Checklist
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