How to create a QR code: tips for a readable, trouble-free code
Making a QR code takes seconds, but a code with the wrong size, low contrast or the wrong type may not scan. Here is a short checklist to know before you print.
What kind of information can you put in?
- A web address or plain text.
- A Wi-Fi connection: a phone that scans the code joins without typing the network name and password.
- WhatsApp: opens a chat with your number directly, optionally with a prefilled message.
- A business card (vCard): lets people add your name, phone and email to their contacts.
- Email, SMS and phone calls.
What does error correction level mean?
A QR code carries extra information so it can still be read if part of it is dirty or damaged. There are four levels: L (about 7%), M (15%), Q (25%) and H (30%). The higher the level, the denser and busier the code gets. On a clean screen or paper, M is enough. If the code may get wet, scuffed or have a logo placed over it, choose Q or H.
Size, color and margin
- Leave an empty border of at least four modules (the small squares) around the code. The tool calls this setting "Margin".
- Use a dark foreground on a light background. The reverse (light code on dark) does not work with some readers.
- Contrast must be high. Nobody can scan a light yellow code on white.
- A printed code should usually be at least 2 cm wide. If it will be scanned from a distance (like a poster), think of a width of about one tenth of the scanning distance.
The more information, the denser the code
A long address or a contact card with many fields fills the code with tiny squares and makes it harder to scan. Use a short address when you can. If it is too long the tool tells you.
These codes are static
The QR codes we generate are static: the information is inside the code itself, not tied to an account, never expires and does not track how many people scan it. If you want to change where a printed code points later, encode a short redirect address that you control.
Always test before you publish
Scan the code with your own phone before printing or publishing. If you can, try both an iPhone and an Android phone. Now open the QR code generator; the Wi-Fi QR code, WhatsApp QR code and vCard QR code pages open directly on the right tab.
PNG is good for sharing and putting in documents, and SVG is good for large prints because it stays sharp however much you enlarge it.