QR Code Fundamentals

Core concepts every QR code user should understand — from basic structure and versions to encoding modes, error correction, and how scanners decode symbols.

What Is a QR Code? A Complete Introduction

The definitive beginner guide to QR codes — history, structure, how they work, and why they matter in 2026.

QR Code Anatomy: Every Component Explained

Detailed breakdown of QR code components: finder patterns, timing patterns, alignment markers, data regions, and format information.

QR Code Versions 1-40: Size, Capacity, and Selection

Complete reference for all 40 QR code versions — module counts, data capacity per EC level, and how to choose …

Encoding Modes: Numeric, Alphanumeric, Byte, Kanji, and ECI

How QR codes encode data: five modes with different character sets and efficiency. When to use each mode and mixed-mode …

Error Correction Levels L, M, Q, H: How to Choose

Understanding error correction levels and their trade-offs. When to use L (7%), M (15%), Q (25%), or H (30%) recovery.

How QR Code Scanning Works: From Camera to Data

The complete decoding pipeline: image capture, binarisation, finder detection, format reading, unmasking, error correction, and data extraction.

Static vs Dynamic QR Codes: Pros, Cons, and When to Use Each

Compare static and dynamic QR codes: functionality, cost, analytics, flexibility, and which type fits your needs.

QR Code Data Capacity: Maximum Characters by Version and Mode

Complete capacity tables for all 40 versions across all EC levels and encoding modes. How to calculate the required version …

QR Code vs Barcode: Why 2D Won

How QR codes surpassed traditional 1D barcodes: capacity, speed, error correction, and versatility comparison.

Mask Patterns: The Hidden Optimisation in Every QR Code

The eight mask patterns, penalty scoring, and how the encoder selects the optimal mask for readability.

The Finder Pattern: Why QR Codes Have Three Squares

The 1:1:3:1:1 ratio, detection algorithm, and why three squares in specific corners enable instant orientation from any angle.

Reed-Solomon Error Correction in QR Codes

How Reed-Solomon codes work in QR codes: Galois field arithmetic, generator polynomials, and codeword interleaving.

Micro QR and rMQR: Compact Alternatives to Standard QR

When standard QR codes are too large: Micro QR (M1-M4) and Rectangular Micro QR (rMQR) variants for space-constrained applications.

QR Code Standards: ISO 18004 and Beyond

International standards governing QR codes: ISO/IEC 18004, JIS X 0510, GS1 Digital Link, EMV QR, and industry-specific specs.

The History of QR Codes: From Toyota to Global Standard

QR code history from 1994 invention at DENSO WAVE through ISO standardisation, smartphone adoption, and COVID-era boom.