QR Code Generator

1. Enter the text or URL you want to encode.
2. Select an error correction level (L, M, Q, or H).
3. Choose the image size (128, 256, or 512 pixels).
4. Click "Generate QR Code" to create the image.
5. Click "Download PNG" to save the QR code.

What is a QR Code?

A QR (Quick Response) code is a two-dimensional matrix barcode that encodes data in a grid of black and white squares. Invented in 1994 by Denso Wave for tracking automotive parts, QR codes have become one of the most widely used encoding formats in the world. Unlike traditional one-dimensional barcodes that store data only horizontally, QR codes store data both horizontally and vertically, allowing them to hold significantly more information. A single QR code can encode up to 4,296 alphanumeric characters or 7,089 numeric digits, depending on the error correction level and data type.

How QR Code Generation Works

This tool generates QR codes entirely in your browser using JavaScript. When you enter text or a URL, the encoder analyzes the input data, selects the most efficient encoding mode (numeric, alphanumeric, byte, or kanji), applies error correction using Reed-Solomon codes, and arranges the resulting data into a matrix pattern. The error correction level determines how much of the code can be damaged while still being readable: Level L recovers 7% of data, M recovers 15%, Q recovers 25%, and H recovers 30%. Higher error correction produces denser codes but makes them more resilient to physical damage or partial obstruction.

Common Use Cases

• Sharing website URLs on printed materials, business cards, and posters
• Encoding Wi-Fi credentials for easy network access without typing passwords
• Creating vCard contact information for instant contact saving
• Generating payment links and digital wallet addresses
• Restaurant menus, product packaging, and event tickets
• Two-factor authentication (2FA) setup with authenticator apps

QR Code Data Types and Capacity

QR codes support several structured data formats beyond plain text. URLs are the most common payload, but you can also encode phone numbers with the tel: prefix, email addresses with mailto:, SMS messages with sms:, and Wi-Fi configurations using the WIFI: scheme. The maximum data capacity depends on the content type and error correction level. Numeric-only data allows the highest capacity, followed by alphanumeric, then byte (UTF-8) data. When choosing a size for your QR code, larger images are easier to scan from a distance, while smaller codes work well for digital displays where the viewer is close to the screen.

For generating random identifiers, try the Nano ID Generator or the Random String Generator. For encoding and decoding URL data, use the URL Encoder/Decoder.