What is a QR Code?

A QR code (Quick Response code) is a two-dimensional barcode that stores data—such as URLs, payment details, or contact information—and can be quickly scanned with a smartphone camera. Created by DENSO WAVE in 1994, QR codes can hold much more data than traditional barcodes and can be read from any angle, even if partially damaged, thanks to error correction, alignment patterns, and a structured grid of modules. Important components include position and alignment markers, timing patterns, format and version info, data modules, error correction, and a quiet zone for accurate scanning. QR codes are common for payments, marketing, packaging, event tickets, and secure file access.

Delivr, licensed by DENSO, generates ISO-compliant QR codes using both proprietary and patented technology, ensuring high reliability, security, and privacy. Delivr’s platform supports advanced features, including encrypted connections, threat detection, dynamic redirects, and privacy-first deployments. With over 15 years of experience and a 99.9% uptime record, Delivr powers millions of QR code connections worldwide, offering trusted, enterprise-grade solutions for marketing, commerce, and secure interactions.

Decoding the Structure of a QR Code.

A QR code consists of small black-and-white squares called modules, each representing binary data (0s and 1s). Their arrangement enables scanners to decode the information accurately, no matter the code’s orientation. Each part of this grid has a specific function:

• Position Markers. Large squares in three corners that help scanners locate and correctly read the code from any angle.
• Alignment Markers. Smaller squares that compensate for distortion, ensuring accurate scanning even on curved or uneven surfaces.
• Timing Patterns. Alternating black-and-white lines between position markers that define the grid’s size and help the scanner correctly map each module.
• Format Information. Encoded near the position markers, this stores details such as the error correction level (L, M, Q, H) and the mask pattern applied to the data modules. It helps the scanner interpret the QR code’s layout before decoding the actual data.
• Version Information. Version Information indicates the QR code’s version number, which determines its size and data capacity. It ensures the scanner knows exactly how to map and read the modules.
• Data Modules. The area containing the actual encoded information, which can range from plain text and URLs to complex data like payment instructions.
• Error Correction (ECC). Built-in redundancy that allows the code to remain readable even if parts are damaged, obscured, or missing.
• Quiet Zone. The Quiet Zone is the blank margin surrounding the QR code, typically at least four modules wide on all sides. It acts as a buffer, separating the code from any surrounding text, graphics, or background patterns, so scanners can clearly identify where the QR code starts and ends. Without a proper quiet zone, scanning reliability drops significantly.

How do QR codes work?

When you scan a QR code, your phone’s camera captures the image, and the decoding software interprets the pattern of black-and-white modules. In seconds, it can open a website, process a payment, add a contact, or perform other predefined actions.

1. Encoding the Data

• A QR code starts with information you want to share (text, a URL, payment details, etc.).
• This data is converted into binary (0s and 1s).
• The binary is arranged into modules—tiny black or white squares in a specific pattern according to the QR code standard.
• Error correction (ECC) is added so that the code remains readable even if partially damaged.
• A mask pattern is applied to balance the distribution of black and white modules, improving scanning reliability.

2. Printing or Displaying the Code

• The finished grid is rendered as a visual pattern and placed with a quiet zone around it.
• QR codes can be printed, displayed on screens, or embedded in documents.

3. Scanning the Code

• A camera or QR scanner captures the image.
• The scanner first detects the position markers to locate the code and determine its orientation.
• Alignment markers and timing patterns help map out the module grid precisely.

4. Decoding the Data

• The scanner reads the format information (error correction level + mask pattern) and, if present, the version information.
• The mask is removed to restore the original binary pattern.
• The binary sequence is interpreted according to the encoding mode (numeric, alphanumeric, byte, Kanji, etc.) to reconstruct the original data.

5. Using the Information

• If the data is a URL, the device can open it in a browser.
• If it’s payment data, contact details, or other structured information, the device’s software can process it accordingly.

Why are QR codes so reliable?

QR codes are designed to be fast, flexible, and damage-resistant:

• 360° readability: Scans from any direction
• Error correction: Up to 30% of the code can be damaged and still work (thanks to Reed-Solomon error correction)
• Works on curved surfaces: Thanks to alignment patterns
• Supports multiple languages
• Compact but powerful: Can store 200x more data than a traditional barcode

Who owns the rights to QR codes?

DENSO WAVE holds the patent for the QR code, but its specifications are open and free to use worldwide. Delivr is proud to be one of a handful of companies globally licensed by DENSO to generate ISO-compliant QR codes, ensuring accuracy, durability, and security at every scan.

What are QR codes used for?

QR codes bridge the gap between physical and digital. Common use cases include:

• Payments (Scan & Pay)
• Marketing & Advertising
• Product Packaging (How-to videos, ingredients, AR)
• Event Tickets & Check-ins
• Touchless Menus
• Business Cards & Networking
• Loyalty Programs
• Secure File Access
• Logistics & Inventory

The platform you use to generate your QR codes is as important as the reason you generate them.

There are three variables you can’t control in the QR world:

1. The device being used
2. The operating system
3. The scanner app

But you can control the code itself.

Delivr helps you do just that—with precision, performance, and privacy.

Delivr has been a leader in QR code technology since 2008, with over 15 years of proven reliability and a 99.9% uptime track record.

Delivr generates ISO-compliant QR codes and are officially licensed by DENSO—the inventor of the QR code. Delivr’s platform offers patented and proprietary solutions, built for secure, privacy-first deployments.

Delivr is trusted by the world’s leading brands that prioritize analytics, compliance, and consumer trust. We've supported thousands of businesses and over a million creators, powering more than 100 million direct connections across 250+ countries, territories, and regions, in over 200 languages and dialects.

Delivr also delivers the highest-performing landing pages in the industry—designed for speed, conversion, and seamless user experience.

How Delivr secures your QR codes.

QR codes are inherently secure, but can be misused by attackers if you're not cautious. That's why source and technology matter.

• Encrypted Connections (HTTPS, AES-256) keep data safe during scans.
• Threat Detection blocks malicious links and suspicious scanning patterns.
• Access Controls, such as 2FA and SSO, prevent unauthorized use.
• Dynamic Redirects let you update or disable QR codes at any time.
• Privacy by Design ensures no personal data is collected or exposed.
• Compliance with laws like GDPR and CCPA protects user rights.
• Brand Protection Tools help detect fakes and ensure product authenticity.

This ensures your QR codes are both trusted and tamper-resistant, making them safe for enterprise, government, and consumer use.