QR Code Guide — Create & Use QR Codes Online

Quick Response (QR) codes store data in a 2D barcode that cameras and phone apps can read instantly. They are everywhere — menus, payments, tickets and marketing.

What can a QR code contain?

• Website URLs
• Plain text
• Wi-Fi credentials
• Contact details (vCard)
• Payment links (including UPI)

The more data you encode, the denser (and harder to scan) the pattern becomes. For marketing, short URLs work best.

How scanning works

1. Camera captures the pattern.
2. Software locates finder patterns and decodes modules.
3. The payload is interpreted (open URL, show text, etc.).

Modern phones scan from the native camera app — no separate app required.

Best practices

Size and contrast

• Minimum ~2 cm print size for close scanning.
• Dark modules on light background with quiet zone (margin).

Test before printing

Scan from multiple devices and distances.

Use HTTPS links

Especially for public marketing — builds trust and enables analytics on your site.

Track campaigns

Use unique landing URLs per campaign rather than one generic homepage link.

QR vs barcode

Barcodes are 1D and typically hold a product ID. QR codes are 2D and hold much more flexible payloads.

Generate QR codes free

Use MerQPrime’s QR code generator — enter a URL or text, download PNG, no sign-up. Processing happens in your browser.

For UPI payments specifically, see our UPI QR guide.