Hi everyone,
QR has complex behaviors:
A QR code can store a variable amount of data depending on its *version* (size of the QR code), *error correction level*, and *encoding mode*. Here’s a breakdown of these factors:
### 1. **QR Code Versions**- QR codes come in **40 versions**.
- The **version** determines the size (number of modules or dots) of the QR code.
- Version 1 is the smallest, with a size of **21x21 modules**.
- Each subsequent version adds 4 modules per side (Version 2 is 25x25, Version 3 is 29x29, and so on).
### 2. **Error Correction Levels**QR codes contain error correction data to allow recovery if the code is damaged. There are four levels:
- **L (Low)**: Corrects up to 7% of errors.
- **M (Medium)**: Corrects up to 15% of errors.
- **Q (Quartile)**: Corrects up to 25% of errors.
- **H (High)**: Corrects up to 30% of errors.
The higher the error correction level, the fewer data can be stored, as more space is used for error correction.
### 3. **Encoding Modes**QR codes support various encoding modes to store different types of data:
- **Numeric (numbers only)**: The most efficient (3 digits per 10 bits).
- **Alphanumeric**: Supports the characters 0-9, A-Z (uppercase), and some special characters like `Space`, `$`, `%`, `*`, `+`, `-`, `.`, and `/`.
- **Byte Mode**: Encodes data as 8-bit bytes, such as ASCII, UTF-8, or binary data.
- **Kanji Mode**: For encoding Japanese characters.
### 4. **Maximum Storage Capacity**
The maximum storage capacity of a QR code depends on the version, error correction level, and encoding mode.
Below are examples of how many characters a QR code can store based on version and error correction level (Version 1 to 40, error correction levels **L**, **M**, **Q**, **H**):
### Summary
- **Capacity**: QR codes can store anywhere from a few characters to thousands, depending on version and error correction level.
- **Modes**: Numeric, Alphanumeric, Byte, and Kanji are the supported encoding modes.
- **Error Correction**: Higher error correction levels reduce storage capacity but improve readability if damaged.