What a QR code can encode
A QR code can store any text data, up to about 3,000 characters depending on the error correction level. In practice, QR codes are used for URLs (the most common case), plain text, contact information (vCard format), Wi-Fi credentials, email addresses, phone numbers, and payment information.
The most common use case by far is encoding a URL. A user scans the QR code and is taken directly to the URL without typing it. For physical marketing materials — flyers, signs, product packaging — this is the easiest way to bridge physical and digital.
Shorter URLs produce simpler QR codes with fewer modules, making them easier to scan. If your URL is long, consider using a URL shortener before encoding it.
- URL / website link
- Plain text
- Email address
- Phone number
- SMS
- Wi-Fi network credentials
- vCard contact information
- Geographic coordinates
Error correction and scanning reliability
QR codes have built-in error correction that allows them to be scanned even if part of the code is obscured or damaged. There are four error correction levels: L (7% can be damaged), M (15%), Q (25%), and H (30%).
For codes that will be printed on materials that might get dirty or partially obscured, use level M or Q. Level H allows up to 30% damage — this is used for branded QR codes where a logo is placed in the center, deliberately covering part of the code.
A higher error correction level means the QR code requires more modules to store the same data, making the code denser and potentially harder to scan at small sizes. For a clean URL on a screen, level M is the standard choice.
Generating and downloading a QR code
The Irreva QR Code Generator creates a QR code from any URL or text instantly. You can set the size in pixels and download the code as a PNG image for use in print or digital projects.
For print use, generate the QR code at the largest size available and use a vector format (SVG) if your application supports it. Vector QR codes scale to any size without pixelation, which is essential for large-format printing like posters and banners.
Always test your QR code before printing or publishing. Scan it yourself with two different devices to confirm it works and leads to the correct destination. Check that the URL it encodes is live and loads correctly.