Why check
A code that reads once is not a code that works
Most QR codes are checked by pointing a phone at them on a screen and calling it done. Then they go on a 25 mm sticker, or a menu that fades in the sun, and stop scanning. This reader runs the same four tests the generator runs on its own output: the image as uploaded, at half and a quarter of its size, and with its contrast washed out. If a supplier sent you a code, this is how to find out before you print five thousand of it.
FAQ
Frequently asked questions
- Which images can it read?
- PNG, JPEG, WebP, GIF and SVG files, pasted screenshots, and photos taken with your phone camera. A straight, sharp image with a little white space around the code reads best.
- Is my image uploaded anywhere?
- No. The code is decoded inside your browser with the same engine the generator uses for its scan check. The image never leaves your device.
- What does “fragile” mean?
- The code reads at full size but fails when shrunk to a quarter of its size or when its contrast is washed out — the conditions of a small sticker or a cheap print. It works today and may fail later. Regenerate it with a simpler shape, a smaller logo or higher error correction.
- Is it safe to open the link?
- A QR code can point anywhere, which is exactly why this page shows you the address first. Check the domain before opening it, the same way you would with a link in an email.
Need a new one?
The generator makes codes that pass these tests before you download them, in every format, free.