QR Code Tools

QR codes store their data with deliberate redundancy, a scheme called Reed–Solomon error correction. At the highest setting, Level H, roughly 30% of the code can be covered or damaged and a scanner can still reconstruct the original data — which is why a logo in the centre does not stop it working. If you add one, choose a high error-correction level and test the result with two or three phones before sending it to print.

Because it has to see the code to decode it, and browsers deliberately refuse camera access until you approve it. The video feed is read and decoded on your own device; no image or frame is uploaded anywhere. Denying permission simply stops the scanner from working — it has no fallback.

No, and that is worth understanding. These are static codes: the data is encoded directly into the pattern, so the image works forever and does not depend on Mavertex staying online. The trade-off is that the destination cannot be changed afterwards. If you need to redirect a printed code later, encode a URL you control and change where that URL points.

A common rule of thumb is that the code should be about a tenth of the distance it will be scanned from — roughly 2cm for a code read at arm's length on a flyer, and much larger for a poster read from across a room. Keep a clear quiet zone of blank space around all four edges, since scanners use it to find the code's boundary.

Treat one exactly as you would an unfamiliar link, because that is what it usually is. A code can encode any URL, and the pattern gives you no visual clue where it leads. Our scanner shows you the decoded text and waits rather than opening it automatically, so read the address before you tap. Be especially wary of codes stuck over an existing one on parking meters or payment terminals, which is a common scam.