Generate and read QR codes online

QR codes: generation, customization, and scanning

QR (Quick Response) codes are two-dimensional barcodes that encode text, URLs, Wi-Fi credentials, contact information, or any other data into a grid of black and white modules. They were invented in 1994 for automotive manufacturing but became ubiquitous for consumer use thanks to smartphone cameras that can decode them instantly.

A QR code's capacity depends on the data type and error correction level. At the lowest error correction (Level L, 7% recovery), a QR code can hold up to 7,089 numeric characters or 4,296 alphanumeric characters. URLs typically use 50-200 characters, well within capacity. Higher error correction levels reduce capacity but allow the code to be read even when partially damaged or obscured.

Custom colors make QR codes match your brand identity. The only requirement is sufficient contrast between the module color (traditionally black) and the background color (traditionally white). Dark modules on light backgrounds work best. Avoid low-contrast combinations like light gray on white, which scanners may fail to read.

The reader functionality uses the browser's BarcodeDetector API to decode QR codes from uploaded images. This is useful for extracting URLs from screenshots, reading Wi-Fi passwords from photos of router labels, or decoding any QR code you cannot scan with your phone's camera (because it is on your computer screen, for example).

Common use cases

• Marketing materials: Generate QR codes linking to landing pages, app downloads, or promotional offers for print materials like business cards, flyers, posters, and product packaging.
• Wi-Fi sharing: Create QR codes that automatically connect devices to your Wi-Fi network when scanned, eliminating the need to type long passwords manually.
• Event check-in and ticketing: Generate unique QR codes for event tickets, conference badges, or reservation confirmations that can be scanned for quick verification.
• Restaurant menus and ordering: Create QR codes linking to digital menus, ordering systems, or review pages that customers can access by scanning from their table.

Technical details

Encoding capacity

Up to 7,089 numeric characters, 4,296 alphanumeric characters, or approximately 860 bytes of binary data at error correction level L.

Error correction

Level L (7% recovery) for maximum data capacity. Higher levels (M: 15%, Q: 25%, H: 30%) allow partial damage tolerance at the cost of reduced capacity.

Export formats

PNG (raster, any size) and SVG (vector, infinitely scalable). SVG is preferred for print materials where the QR code may be reproduced at various sizes.

Reader API

Uses the BarcodeDetector API (Chrome, Edge, Android browsers). Decodes QR codes from uploaded images by analyzing the pixel pattern against the QR specification.

How to generate a QR code online

Create a QR code from text or a URL and download it.

1. Type or paste the content you want to encode.
2. Customize module size, foreground, and background colors.
3. Download the QR code as PNG or SVG, or copy the SVG markup.
4. Switch to the Read tab to decode a QR code from an image.

Frequently asked questions