Static codes: what that means for you
Every code made here is static. Your link, text or contact data is written directly into the pattern of squares. There is no short link in between, no redirect through our servers and no account that has to stay active. A code you print today will work for as long as the thing it points to exists.
Dynamic QR services work differently. They encode their own short address and forward visitors, which lets them count scans and change the destination later, but the code stops working if you stop paying. If you do not need analytics, a static code is simpler and safer.
Error correction and why it matters
QR codes carry built-in redundancy so they can still be read when dirty or damaged. There are four levels. L restores about 7 percent of the data, M about 15 percent, Q about 25 percent and H about 30 percent. Higher levels make the pattern denser, so the squares get smaller for the same size of code.
Medium is a good default for screens and clean prints. Choose Q or H for stickers, packaging, outdoor signs or anything likely to get scratched. When you add a logo in the center, the tool raises correction to H automatically, since the logo covers part of the code.
Size, margin and contrast
The blank border around a code is called the quiet zone. Scanners need it to find the edges, so keep the margin at four modules or more. Cropping it for a tight design is the most common reason a code fails to scan.
Dark squares on a light background scan best. Inverted codes, with light squares on a dark background, are not read by some older apps. The tool warns you when the contrast between your two colors is too low. As a size guide, a printed code should be at least 2 cm wide for close scanning, and larger the farther away people will be: roughly one tenth of the scanning distance.
Which format to download
PNG is a pixel image and suits websites, documents and chat. Pick a size big enough for your use; 1000 pixels is plenty for most prints. SVG is a vector file that stays sharp at any size, so use it for posters, signs and anything a printer will resize.
Before you print a batch, scan the code with two different phones and test it at the final size. A quick check can save a whole print run.
What you can encode
Besides web addresses, you can encode plain text, a Wi-Fi login, a contact card, an email with subject and body, a phone number, a pre-filled text message and a WhatsApp chat link. Each type is stored in a standard format that phone cameras recognize without a special app.