Every term you need to understand QR code generation, scanning, and standards — from error correction levels to UPI payment codes. Each definition links to the relevant QRPress tool or guide.
A two-dimensional matrix barcode defined by ISO/IEC 18004 that encodes data in a pattern of black and white squares. QR codes can store up to 4,296 alphanumeric characters and are readable by any modern smartphone camera without a dedicated app.
Free QR Code Generator →A QR code whose data is encoded directly into the pixel pattern. The destination or content is permanent — it cannot be changed after generation. Static codes are free, require no account, and work offline because the payload lives in the image itself.
Static vs Dynamic QR Codes →A QR code that stores a short redirect URL instead of the final destination. The redirect target can be changed at any time without reprinting the code. Dynamic codes also enable scan analytics (counts, device types, countries). They require a redirect service to stay active.
Free Dynamic QR Code Generator →A QR code setting that determines how much damage the code can sustain while remaining scannable. Four levels exist: L (7% recovery), M (15%), Q (25%), and H (30%). Level H is used when adding a center logo because up to 30% of modules can be obscured.
How to Create a QR Code with Logo →Data collected each time a dynamic QR code is scanned, including timestamp, device type, browser, country, and referrer. Analytics help measure campaign performance. Static QR codes cannot provide scan analytics because no server is involved in the decode.
Data Flow & Privacy →A QR code that encodes a UPI payment deep link (upi://pay?pa=...&pn=...) so customers can scan and pay using Google Pay, PhonePe, Paytm, BHIM, or any UPI-compatible app. The QR follows NPCI specifications and is the standard payment method at shops across India.
Free UPI Payment QR Code Generator →A QR code that encodes contact information in the vCard 3.0 format (RFC 2426). Scanning opens the contact card on iOS or Android, allowing the user to save the name, phone, email, company, and address with one tap.
Free vCard QR Code Generator →A QR code that encodes WiFi network credentials in the MECARD/WPA format: WIFI:S:<ssid>;T:<auth>;P:<password>;;. Scanning configures the phone to join the network automatically — no typing the password. Works with WPA, WPA2, WEP, and open networks.
Free WiFi QR Code Generator →A URL that opens a specific page or screen inside a mobile app rather than a browser. Dynamic QR codes can use deep links so scanning opens the app directly (e.g., myapp://product/123) instead of a web page.
Static vs Dynamic QR Codes →The server-side mechanism behind dynamic QR codes. The code encodes a short URL (e.g., api.qrpress.in/r/xyz) that points to a redirect service. On scan, the server looks up the current destination and forwards the visitor with an HTTP 302 redirect.
Data Flow & Privacy →The international standard that defines the QR code symbology, including encoding modes, error correction using Reed-Solomon codes, and symbol versions from 21×21 modules (Version 1) to 177×177 modules (Version 40). Current revision: ISO/IEC 18004:2024.
QR Code vs Barcode →The blank margin around a QR code that helps scanners distinguish the code from its surroundings. The standard requires a quiet zone of at least 4 modules wide on all sides. Insufficient quiet zone is a common cause of scan failures on printed materials.
Best QR Code Size for Printing →