A QR code is an address rewritten as an image that a phone reads with its camera. It belongs wherever people have nothing to click on: a poster, a business card, packaging, a menu or a slide.
A QR code for every link
On skrat.im every short link gets a QR code automatically. After shortening, click QR code to see a preview and download links in SVG and PNG. The code is also available straight from the address: add .png or .svg after the short link.
https://skrat.im/concert.png?size=1024
https://skrat.im/concert.svg?fg=1a4ed8&bg=ffffffThe fg and bg parameters set the foreground and background colours, size the PNG width in pixels (64 to 2048) and margin the white border in modules.
Why encode a short link rather than a long address
A QR code of a long address has many tiny squares. The more there are, the bigger the printed code has to be for a camera to read it, and the more sensitive it becomes to creases and bad light. A short link like skrat.im/abc gives a code with chunky, easily readable modules.
The second reason is practical: a printed code cannot be changed, a short link can. When the destination page changes, edit the link and every poster with the code keeps working. And since each scan is a click on the short link, the statistics show how many people actually scanned it.
Printing a QR code properly
- Keep a white margin around the code at least one module wide; skrat.im adds it automatically.
- Keep the contrast: dark modules on a light background. Some phones cannot read inverted codes.
- The minimum size on paper is about 2 × 2 cm for a code made from a short link. For a poster read by passers-by plan a bigger code: roughly a tenth of the distance it should be scanned from.
- Before printing, scan the code from the screen and from a test print.
What to write under the code
People scan more willingly when they know what to expect. A short line such as “Programme and tickets” raises the number of scans more than any decoration. If you use a custom alias, print the link itself under the code too: anyone without a phone at hand can type it.
Frequently asked questions
Which QR code format should I use for print?
SVG. It is a vector, so it scales to poster size without blurring. Use PNG on the web and in documents that cannot embed SVG.
Can I change where a QR code leads after printing?
If the QR code encodes a skrat.im short link, yes: change the destination of the link and the printed code keeps working. If it encodes the long address directly, no.
Does a QR code expire?
No, as long as the link it encodes is valid. On skrat.im links do not expire unless you set an expiry yourself.