How a QR code works
A QR code (Quick Response code) is a two-dimensional barcode that can store text, links, contact details, and other kinds of data as a pattern of black and white squares. Any phone camera with a QR reader can decode the content just by pointing at the image, no typing required.
Which size and error correction level to choose
For on-screen use (website, email, social media), 300px is usually enough. For print, especially on small materials like business cards, use 400px or 500px to keep it sharp even at lower print resolution. As for error correction, most cases work fine with level M (medium). If you plan to overlay a logo in the center of the QR code, or it will be printed on a surface prone to wear, use level H (very high), which tolerates up to 30% damage without losing readability.
Tips for a QR code that actually works
Keep strong contrast between the code color and the background — colors that are too close to each other make the code hard or impossible for a camera to read. Avoid similar tones for the two colors, and always test the generated QR code with a phone before using it in a final piece, whether digital or printed.
What types of QR codes you can create
Pick the type at the top of the form and fill in only that type's fields — the correct technical format is built automatically:
- Link or text: any address or free-form message.
- Wi-Fi: whoever scans it connects straight to the network, no password typing.
- Contact (vCard): opens the "add contact" screen with name, phone, and email pre-filled.
- Email: opens the mail app with recipient, subject, and message ready to send.
- Phone: starts a call to the number provided.
- SMS: opens the messaging app with number and default text pre-filled.
- Location: opens a maps app pointed at the given latitude and longitude.
- Event (calendar): offers to add the event to the phone's calendar, with date, time, and location.
A read-only field shows exactly what will be encoded, in case you want to double-check it or reuse the text elsewhere.