QR Code Scanner

How it works

Decoding runs entirely through the open-source jsQR library in your browser: for a camera scan, each video frame is drawn to a hidden canvas and its raw pixel data is handed to jsQR on every animation frame until a code is found; for an uploaded image, the same pixel-data decode runs once against the full picture. Nothing is ever uploaded anywhere to be read.

FAQ

Why does the camera option default to the rear camera on my phone?

It requests facingMode: 'environment', which tells the browser to prefer the back-facing camera — the one you'd naturally point at a physical QR code — though you'll still need to grant camera permission for it to work at all.

Why does scanning a photo of a QR code sometimes fail?

jsQR needs enough contrast and resolution to find the code's three corner finder patterns; a blurry, heavily tilted, or very low-resolution image can fail to decode even when the QR code itself is perfectly intact.