A QR code is nothing more than a square of black and white dots, yet scanning one can feel like a small mystery when nothing happens on screen. The reassuring part is that every phone made in the last several years can read them, and the reasons a code refuses to scan are almost always simple: the camera is too close, the lighting is wrong, or the wrong app is open.
Scanning With the iPhone Camera
You do not need to install anything. Open the built-in Camera app, point it at the code and hold the phone roughly 15–25 cm away. After a moment a yellow banner appears at the top of the screen; tap it to open the link. If nothing ever appears, go to Settings › Camera and switch on Scan QR Codes. Every iPhone running iOS 11 or later supports this, so the feature is already in your pocket.
Scanning on Android
Most Android phones from 2018 onward have a reader inside the default camera. Open the Camera, aim at the symbol and tap the prompt or button that pops up. Samsung, Google Pixel and Xiaomi devices each phrase it a little differently, but the flow is the same: point, wait, tap. If your camera truly has no scanner, install a well-reviewed scanner from the Play Store and grant it camera access.
WeChat, Alipay and In-App Scanners
In Asia many people scan from inside an app rather than the camera. In WeChat, tap the ＋ icon and choose Scan; in Alipay, tap the scan icon on the home screen. These in-app readers handle payment and loyalty codes that a plain camera may only show as text. If one app shows a raw URL instead of opening it, try another — the code itself is fine, it is just being interpreted differently.
Scanning From a Browser or Desktop
With no phone handy, you can still read a code. Open a browser-based scanner, allow access to your webcam, and hold the printed code in front of the lens. This is handy for checking your own codes before you print a batch. It is also the quickest way to confirm a link works before it goes on a poster.
When a QR Code Will Not Scan
If you have tried more than one app and still get nothing, work through these checks in order:
- Clean the lens and the code. Fingerprints on the camera and dust on the print are the most common culprits;
- Change your distance. Move slowly from about 10 cm to 30 cm and pause at each step;
- Kill the glare. Angled light on a glossy screen or laminated menu washes out the contrast — tilt the phone or shade the code;
- Improve the light. Very dim rooms and hard shadows both break detection; add soft, even light;
- Flatten the surface. A code on a curved bottle or a folded flyer is distorted and hard to lock onto.
Once you are making your own codes, run them through the steps in our QR code testing checklist so real users never hit these problems. If you would rather start from scratch, use a QR code generator and create a QR code free with QR StarCode before you print.