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QR Brand Studio

How QR Codes Work

Discover the fascinating technology behind QR codes, from data encoding methods to sophisticated error correction algorithms that ensure reliability.

Matrix Barcode Technology

QR codes are two-dimensional matrix barcodes that store information in a square grid of black and white modules. Unlike linear barcodes that store data horizontally, QR codes utilize both horizontal and vertical space, enabling massive data density.

💡 A single QR code can store up to 7,089 numeric characters or 2,953 alphanumeric characters

QR Code Structure & Components

Essential Components

Finder Patterns

Three square patterns in corners that help scanners locate and orient the code

Alignment Patterns

Smaller squares that help correct for perspective distortion

Timing Patterns

Alternating modules that establish coordinate system

Quiet Zone

White border that separates QR code from surroundings

Version & Capacity

40 Different Versions

  • • Version 1: 21×21 modules
  • • Version 40: 177×177 modules
  • • Each version adds 4 modules per side

Data Capacity

  • • Numeric: Up to 7,089 digits
  • • Alphanumeric: Up to 4,296 characters
  • • Binary: Up to 2,953 bytes
  • • Kanji: Up to 1,817 characters

Data Encoding Process

Step-by-Step Encoding

1

Mode Selection

Algorithm determines the most efficient encoding mode: Numeric, Alphanumeric, Byte, or Kanji

2

Character Count

Data length is encoded using a character count indicator specific to the chosen mode

3

Data Conversion

Characters are converted to binary using the selected encoding mode's rules

4

Error Correction

Reed-Solomon error correction codes are generated and appended to the data

✅ Encoding Modes

Numeric Mode

Most efficient for digits 0-9. Groups digits in sets of 3 for optimal compression.

Alphanumeric Mode

Supports 45 characters including letters, digits, and common symbols.

Byte Mode

Raw binary data mode. Can store any 8-bit data including UTF-8 text.

📊 Efficiency Comparison

Numeric3.3 bits/char
Alphanumeric5.5 bits/char
Byte8 bits/char

Smart Optimization: QR encoders automatically switch between modes to minimize data size.

Error Correction Technology

Reed-Solomon Algorithm

How It Works

Reed-Solomon error correction treats data as coefficients of polynomials over finite fields. This mathematical approach enables both error detection and correction without requiring retransmission.

Key Benefits
  • • Corrects burst errors (consecutive damaged modules)
  • • Handles random errors distributed across the code
  • • Works with partial occlusion (logos, damage)
  • • No retransmission required

Error Correction Levels

L (Low)~7%

Recovers up to 7% of damaged codewords

M (Medium)~15%

Recovers up to 15% of damaged codewords

Q (Quartile)~25%

Recovers up to 25% of damaged codewords

H (High)~30%

Recovers up to 30% of damaged codewords

Masking and Optimization

Data Masking

  • • Prevents large areas of same-colored modules
  • • Improves scanner readability
  • • 8 different mask patterns available
  • • Algorithm selects optimal pattern automatically

Format Information

  • • Error correction level indicator
  • • Mask pattern reference
  • • Protected by BCH error correction
  • • Duplicated for redundancy

Scanning & Decoding Process

From Image to Data

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Image Capture

Camera captures image and converts to grayscale for processing

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Pattern Detection

Algorithm locates finder patterns and determines orientation

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Data Extraction

Modules are sampled and decoded using error correction

Advanced Scanning Features

  • • Perspective correction for angled scans
  • • Automatic brightness and contrast adjustment
  • • Multiple QR code detection in single image
  • • Motion blur compensation
  • • Low-light enhancement algorithms
  • • Real-time continuous scanning

Technical Standards & Specifications

International Standards

ISO/IEC 18004

Primary international standard for QR code specification

JIS X 0510

Japanese Industrial Standard (original specification)

ANSI/AIM BC11

American National Standard for QR codes

Performance Specifications

Minimum Size

2cm × 2cm for reliable smartphone scanning

Scanning Distance

Up to 10× the QR code width for optimal performance

Decode Speed

Milliseconds on modern devices with good algorithms

Apply This Technology

Now that you understand how QR codes work, create your own with our advanced generator.