Open QR Maker

Why Won't My QR Code Scan?

Check seven common causes of QR code scan failures.

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The QR code may look correct while the camera fails to recognize it. Most failures come from size, contrast, spacing, damage, or encoded content. Check each factor in order.

  1. The Code Is Physically Damaged

Smudging, fading, scratches, water, and sunlight can damage a printed code. Compare a failing print with the original export. Outdoor materials may need lamination, UV-resistant ink, or another protective finish.

  1. The Code Is Too Small For The Distance

A code that scans fine on your monitor at arm's length might be unreadable at the intended scanning distance. The size guide covers the common 10:1 sizing rule of thumb (code size ~ scan distance ÷ 10). If you printed a ¾ in code for a poster that gets viewed from 10 ft away, the modules will be too small for the camera to read.

  1. The Contrast Is Too Low

QR scanners require a clear distinction between dark and light modules. Custom colors can reduce that contrast and prevent scanning.

Convert the colors to grayscale in an image editor and compare their values. Increase the difference if the dark and light modules appear similar. Test the exported code after every color change.

  1. The Logo Is Too Big

A logo overlay covers part of the code. Error correction level H (which Open QR Maker forces when a logo is set) is rated at roughly 30% codeword restoration, but that does not mean you can safely cover 30% of the visible symbol with artwork. Real logos can block finder and alignment patterns long before you hit that number.

Keep the logo small and centered. Test the exported asset on multiple phones before printing because larger overlays can cause intermittent scan failures.

  1. The Quiet Zone Is Missing Or Too Small

The quiet zone is the empty border around the code. The QR specification requires four empty modules on every side. Restore this spacing if the code touches another design element.

Open QR Maker generates the quiet zone for you (defaults to four modules). Make sure nothing overlaps it after you import the SVG or PNG into your design tool.

  1. The Code Is Too Dense For Its Size

A QR code with long content and high error correction has many small modules. At small physical sizes, those modules can fall below the reader's effective resolution. Increase the printed size, shorten the content, or reduce the error correction level.

More information on error correction levels can be found in the error correction levels guide.

  1. You Are Scanning With The Wrong App

Some QR scanner apps support fewer formats than the system camera. For vCard, WiFi, or email payloads, test with the iOS or Android camera app and compare the result with your other scanner.

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