免费 QR Code Reader

工作原理

QR codes are decoded entirely in your browser using a tiny pure-JavaScript library (~30 KB). No image is ever uploaded — even when you use the live webcam scanner.

1. 1
   You drop an image or start the webcam

   For file decoding: the image is loaded into memory. For live scanning: your camera feed stays on your device — frames are captured locally and never transmitted.
2. 2
   Pixels are analyzed by the jsQR library

   jsQR scans the pixel data looking for the QR code's distinctive finder patterns (the three large squares in the corners). Once found, it decodes the data matrix into text.
3. 3
   The decoded text is shown with a type hint

   The tool detects whether the QR contains a URL, Wi-Fi credentials, vCard, email, etc. and labels it accordingly. You can copy or follow safe URLs directly.

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