How to Make Sure Your QR Code Actually Scans (Common Mistakes)

Every QR code failure traces back to one of a small handful of causes. Here's the full list.

Too small for its scanning distance

The most common failure by far. A QR code needs to be roughly one-tenth the width of its intended scanning distance — a code meant to be scanned from ten feet away needs to be at least a foot wide. Shrinking a code to fit a tight layout is the single most common reason a well-designed print piece fails in practice.

Low contrast between the code and its background

Scanners rely on clear contrast between the dark and light modules. A code printed in a light color, on a busy background image, or with insufficient contrast against its surroundings will frequently fail to scan even when it's technically large enough.

No quiet zone around the code

QR codes need a blank margin (the "quiet zone") around all four sides — usually at least four modules' width — so the scanner can clearly detect where the code begins and ends. Cropping a code too tightly, or placing other design elements right up against its edge, breaks this and causes scan failures.

Printed on a curved, reflective, or textured surface

A code printed on a wine bottle's curve, a glossy laminated surface that creates glare, or a heavily textured material can all distort the pattern enough to fail — even though the same code would scan perfectly on flat matte paper.

A logo or graphic covering too much of the code

QR codes have built-in error correction that tolerates a logo covering a portion of the code — but only up to a point (roughly 30% at the highest error-correction setting, less at lower settings). A logo that's too large, or placed over a finder pattern (one of the three corner squares), will break the scan.

The link itself is broken — which is invisible until someone tries

This one doesn't affect the scan — the phone will happily decode the QR code and try to open the link — but if the destination URL is broken, expired, or points to something that no longer exists, the result is the same as a code that doesn't scan at all from the user's perspective.

The fix that solves most of these at once

Use a generator that renders codes with proper error correction and quiet zone by default, test the physical print at actual size and distance before mass-producing it, and — since it costs nothing extra — use a dynamic code so a broken destination link can be fixed instantly instead of requiring a reprint.