What is a QR code and how does it work
A QR (Quick Response) code is a two-dimensional barcode that stores information as a pattern of black and white squares. Unlike traditional barcodes that store data in one dimension (horizontal lines), QR codes store data in two dimensions, allowing them to hold significantly more information — typically up to 4,296 alphanumeric characters. Any smartphone camera can read a QR code instantly, making them ideal for sharing URLs, contact information, payment details, and text.
Common uses for QR codes in Pakistan
Raast payment system uses QR codes for instant peer-to-peer and merchant payments. Bank mobile apps generate QR codes for receiving payments. Restaurant menus have replaced physical menus with QR code digital versions. Government services increasingly use QR codes on documents for verification. WhatsApp Web uses a QR code for linking the mobile app to a computer. Social media profiles, business cards, and product packaging commonly include QR codes linking to websites or social profiles.
QR code types — URL, text, contact, WiFi
URL QR codes link directly to a website when scanned. Text QR codes display a message without opening a browser. Contact (vCard) QR codes let you save a contact instantly to your phone. WiFi QR codes let guests connect to a network without typing a password — ideal for cafes, offices, and hotels. Payment QR codes encode banking details for instant transfers. This generator creates URL and text QR codes that work with any QR scanner app or phone camera.
QR code size and quality for printing
For business cards, a QR code should be at least 2.5 cm (1 inch) square. For posters or signage, size accordingly — a QR code meant to be scanned from 2 meters away should be at least 10 cm square. Always test the printed QR code with a scanner before mass printing. Download the PNG at the highest resolution available for print use.
Frequently Asked Questions
Can a QR code expire? The QR code itself does not expire, but if it links to a URL that goes offline, the code becomes non-functional. If you need long-term reliable QR codes for marketing, use a QR code with a redirect URL that you control.
Is it safe to scan QR codes? Exercise caution with QR codes in public places — malicious QR codes can link to phishing sites or trigger downloads. Always verify the URL before entering any information on a page reached via QR code.