QReator
Free tool

QR code contrast and scannability checker

Most unscannable QR codes fail for four reasons: not enough contrast, inverted colours, an oversized logo, or a dense payload printed too small. Set your colours and options below and get a pass, warning or fail verdict with the reason and the minimum print size in millimetres.

1. Your artwork

2. Verdict

Ready to print

Contrast and sizing are within safe scanning limits for this payload.

Contrast ratio
18.50:1

Scanners need about 3:1. Aim for 7:1 or more on packaging and outdoor print.

Minimum width
30 mm

At 30 cm reading distance, with this payload length. You entered 30 mm.

What to fix

Nothing flagged. Still print one physical proof and scan it under the real lighting.

A short payload is the cheapest way to make a code scannable. Dynamic codes encode a tiny redirect link instead of the full destination, so the grid stays coarse no matter how long the target URL is.

What size should a QR code be for print?Read the full troubleshooting checklist

Questions

How much contrast does a QR code need?
Aim for a contrast ratio of 4.5:1 or higher between modules and background; below 3:1 many camera apps stop locking on, especially under warm indoor light or behind laminate.
Why is a light code on a dark background risky?
Scanners expect dark modules on a light background. Inverted codes work on some phones and fail on others, so it is a coin flip you can't control once the material is printed.
How big can a logo be?
The logo eats the same redundancy that error correction provides. At level Q you have about 25% to spend, at H around 30% — but never let the logo touch the three corner finder patterns.

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