QR Code Scanner

Scanning a QR code is the reverse of generating one: the tool captures a video frame or an uploaded image, locates the three corner finder patterns to work out the code's position and rotation, then reads the grid of modules back into binary and reconstructs the original bytes using the same Reed-Solomon error correction that was used to encode it. Because that decoding step is generic, this scanner works on any QR code regardless of what generated it — a WiFi credential block, a mailto: link, a plain URL, a vCard, or arbitrary text.

This is useful whenever you need to read a code that isn't on your own phone's default camera flow — checking a code before deciding whether to open the link it contains, pulling a WiFi password off a printed sign, extracting text from a poster or menu, or verifying that a QR code you generated actually contains what you intended. The image upload option is also handy for codes buried inside a screenshot or PDF, where holding a camera up to a screen is inconvenient.

Scan reliability depends mostly on image quality: even, glare-free lighting, a code that fills a reasonable portion of the frame, and a sharp, in-focus capture all matter more than camera resolution. If a scan keeps failing, try moving closer, reducing glare, or increasing the image contrast before assuming the code itself is damaged.