QR Codes Aren’t Just Convenient – They Can Be a Hidden Threat

You see them everywhere

How QR Codes Work and Where the Risk Lies

• The binary foundation: Each black or white square in a QR code stands for a 1 or 0, forming a pattern that translates into text, URLs, or other data. The size of the code affects how much information it can hold — small codes pack in less, larger ones hold more. Most use black squares on a white background for best scanning results, though variations exist.
• Your phone’s role: When you scan a code, your device’s camera captures the image and uses algorithms to decode the pattern. It then turns that data into a URL or action — like opening a website. This process happens in real time, with no extra step.
• The quiet zone and corner markers: QR codes have built-in design features — like a blank border (the quiet zone) and corner squares — that help scanners identify where the code starts and how to align themselves. If someone tampers with those elements, the scan might fail or misread the data, which can be used to trick users or cause errors.

Even though QR codes are simple, they’re not inherently safe. If you get a code from a stranger, from an unknown source, or in a strange context — like a flyer at a crowded event — pause before tapping. Don’t just click. Check the URL. Look at the source. And if you’re on a phone that runs security software, use it to scan links before opening them.

You don’t have to avoid QR codes — just don’t take them at face value. A quick second glance can go a long way in keeping your data safe.