QR Code
Render any string as a scannable code
A QR code is a two-dimensional barcode that stores data in a grid of black and white modules, with three large squares in the corners so a scanner can find and orient it regardless of angle. Capacity depends on the version — the grid size — and on what you encode: numeric data packs tightest, then uppercase alphanumeric, then arbitrary bytes.
Every code also carries Reed-Solomon error correction, at one of four levels. That redundancy is why a code still scans with a logo covering the middle or a coffee ring across one corner. It is also why the same content produces a denser grid at higher correction levels: the recovery data has to go somewhere.
How to use it
- Enter what the code should containA URL is the common case, but plain text, a phone number, an email address or Wi-Fi credentials all work. Shorter content means larger, more forgiving modules.
- Pick an error correction levelLevel L recovers about 7% of the code, M about 15%, Q about 25% and H about 30%. Use M for a screen, and H if the code will be printed, laminated or partly covered by a logo.
- Set the size and quiet zoneKeep the blank margin around the code — scanners need it to find the edges. A code printed smaller than about two centimetres square becomes unreliable on a phone camera.
- Download the PNGThe image is rendered on a canvas in this tab, so the URL you encode is never sent anywhere and no tracking redirect is inserted between the scanner and your link.
Frequently asked questions
Do these QR codes expire or stop working?
No. The code is a static image encoding your content directly, so there is no redirect service in between and nothing to expire or bill for. That is also the trade-off: because the content is baked in, changing the destination means generating a new code.
How much data fits in a QR code?
At the largest version with the weakest error correction, roughly 7,000 digits, 4,300 alphanumeric characters or 2,950 bytes. Those limits are theoretical rather than practical — a code that dense needs a good camera and a large print. For anything scanned from a poster, stay well under a couple of hundred characters.
Can I put a logo in the middle?
Yes, if you generate at error correction level H and keep the logo under roughly 30% of the area, centred. The redundancy absorbs the obscured modules. Always test the finished artwork with more than one phone, because scanners differ in how hard they try.
Should I download a PNG or an SVG?
PNG for anything on screen or in a document at a known size. If you need a vector for large-format print, generate at a much higher pixel size — a QR code is pure geometry, so it scales without artefacts as long as the source resolution is high enough that modules stay crisp.
Why does my code fail to scan?
The usual causes are too little contrast, a missing quiet zone, or printing it too small. Inverted colours break many scanners, as does a light module colour on white. Keep dark modules genuinely dark, keep the margin, and test before printing a thousand copies.