QR Code Generator
Create QR codes from URLs, text, Wi-Fi, contact cards, email, phone, SMS, and locations. Free PNG and SVG download.
Utility
QR Code Generator
Generated on April 25, 2026
https://smart-unit-converters.com
Customize appearance
Higher levels recover more data if the QR is dirty or partially covered (good for printed QRs with logos).
Scan with any phone camera to test.
?What is the QR Code Generator?
A QR code (Quick Response code) is a two-dimensional barcode that can hold up to ~4,000 characters of text and is read by every modern smartphone camera in a fraction of a second. This generator turns any URL, plain text, Wi-Fi credentials, contact card (vCard), email, phone number, SMS, or geographic location into a scannable QR code. Generation runs entirely in your browser using the open-source qrcode.js library — your data never touches a server. Download the result as a sharp PNG (great for printing) or a scalable SVG (great for posters, signage, and packaging at any size). Customize the colors, size, quiet-zone margin, and error-correction level to match your brand.
The Formula
QR codes use Reed-Solomon error correction, the same algorithm used by CDs and satellite communications. The data is encoded in a grid of black and white modules and masked with one of 8 patterns to optimize scannability (avoiding long runs of the same color, which confuse cameras). The three large 'finder patterns' in the corners help scanners detect orientation; alignment patterns and timing patterns help them correct for perspective distortion when the code is photographed at an angle. The result is a code that can be read upside down, sideways, partially obscured, or printed on curved surfaces.
QR Code Capacity by Error-Correction Level
Maximum characters that fit at each error-correction level (Version 40, the largest QR size).
| Level | Recoverable damage | Numeric capacity | Alphanumeric | Binary (bytes) |
|---|---|---|---|---|
| L (Low) | ~7% | 7,089 | 4,296 | 2,953 |
| M (Medium) | ~15% | 5,596 | 3,391 | 2,331 |
| Q (Quartile) | ~25% | 3,993 | 2,420 | 1,663 |
| H (High) | ~30% | 3,057 | 1,852 | 1,273 |
Put It in Perspective
A single QR code can hold the entire text of the US Declaration of Independence (~7,800 characters) at low error correction.
QR codes in Japan have been used since 1994 — originally invented by Denso Wave to track car parts on Toyota assembly lines.
China generates over 90 billion QR scans per day — payment QRs (WeChat Pay, Alipay) replaced cash in most retail.
The world's largest QR code is painted on a building roof in China — over 600 metres on each side, scannable from a passing satellite.
Practical Examples
Restaurants put a QR linking to their digital menu on each table — a single code that updates instantly when prices change, with no reprinting.
Wi-Fi QR codes let guests join your network in one tap, no need to type a long password.
Wedding invites include a vCard QR that drops the couple's contact card straight into the guest's phone.
Business cards with a vCard QR — scan once, save the contact forever, no manual typing.
Event posters use a URL QR linking to the registration page, increasing sign-ups by removing typing friction.
Hospitals print a vCard or URL QR on patient wristbands so any nurse can pull up the chart with a phone.
Pakistani retailers print Easypaisa / JazzCash payment QR codes at the checkout for instant mobile payments.
Frequently Asked Questions
Popular Conversions
Jump to a ready-made conversion — useful for quick reference and sharing: