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QR code guides and calculators
Most failed QR codes fail for the same few reasons: printed too small, low contrast, a crowded margin or a link that is too long. These calculators and guides give you the numbers and the fixes before you send anything to print.
All QR code guides and calculators
- Size calculatorHow big a QR code needs to be for the scan distance.
- Contrast checkerWill these two colours scan?
- Error correction demoSee how much of a code can be damaged and still scan.
- TroubleshooterTwelve reasons codes fail, and the fix for each.
- Print size chartBusiness card to billboard, the sizes that work.
Questions
Questions and answers
What is the minimum size for a QR code?
About 2 cm across for a short link scanned at arm's length. For longer distances, divide the distance by ten: a code read from 2 m should be about 20 cm wide.
Which error correction level should I use?
M is the default and right for most print. Use Q or H when the code will get dirty, scuffed or have a small logo over it; the trade-off is a denser code.
Can a QR code be colored?
Yes, as long as the dark modules are clearly darker than the background. Light codes on a dark background work in some scanners but not all, so dark on light is the safe choice.
Why does my QR code not scan?
The common causes are a code that is too small for the distance, low contrast, no clear margin, a stretched or blurry image, or a very long link. The troubleshooter walks through each one.
More free QR code tools
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The next step
Make the code the artwork.
These tools make and check classic codes. AriaQR turns your photo, logo or illustration into the code itself, verified on real decoders before you download, with a link you can edit and track.
