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Technical guides on QR codes, crypto and printing

QR code with a logo: the error budget, and how not to blow it

Adding a logo to a QR code without breaking it: Reed-Solomon budget, real size limit, feathered masking, and the mistakes that make a code unreadable.

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BIP-21, EIP-681, Solana Pay: crypto payment URIs and their traps

The three crypto payment URI standards compared: units, parameters, ERC-20 and SPL token transfers, and the decimal mistakes that cost real money.

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Printing a QR code: size, contrast and scanning distance

What minimum size for a printed QR? What contrast? Business cards, flyers, menus, stickers: concrete rules for a successful scan every time.

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Share Wi-Fi via QR Code: Format, Security & Best Practices

Learn how to generate secure Wi-Fi QR codes using the standard WIFI:T:WPA;S:SSID;P:PASS;; format for homes and offices.

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vCard 4.0: Guide Technique pour une Carte de Visite Numérique par QR Code

Découvrez comment générer une vCard 4.0 optimisée via un QR code client-side, avec gestion des champs, photo et poids.

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QR Code Error Correction: Reed-Solomon Levels L/M/Q/H Explained

Understand how Reed-Solomon error correction works in QR codes, covering L/M/Q/H levels, redundancy mechanics, and logo integration.

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Static vs Dynamic QR Codes: Why web3qr Stays 100% Static

Discover why static QR codes offer superior longevity and privacy compared to dynamic ones, which require servers and accounts.

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QR Code vs Barcode: Capacity, Orientation & Use Cases Explained

Compare QR codes and 1D barcodes like EAN-13. Learn about data capacity, scanning orientation, and when to choose each for retail or marketing.

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8 Reasons Why Your QR Code Becomes Unscannable

Avoid common pitfalls like low contrast, missing quiet zones, and poor error correction to ensure your QR codes are always scannable.

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iCal QR codes for events: Add to calendar in one scan

Generate iCal-compatible QR codes for your events. Instant calendar integration with timezone management and complete VEVENT format handling.

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QR Code GPS géolocalisé : Partager un lieu précis avec geo: URI

Découvrez comment créer un QR code GPS pour partager des coordonnées précises via Google Maps ou Apple Plans, sans serveur ni inscription.

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EAN-13 Structure & Checksum Guide: GS1 Codes vs Internal Use

Master EAN-13 barcode structure, checksum calculation, and the critical difference between official GS1 registration and internal generation.

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Optimize Your Restaurant QR Code Menu: Speed, Hygiene & Design

Learn why heavy PDFs ruin the dining experience and how to optimize your restaurant QR code menu with lightweight alternatives, proper placement, and high-contrast design for dark environments.

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Real Estate QR Codes: Listings, Virtual Tours & DPE Data

Boost real estate marketing with client-side QR codes for listings, virtual tours, and DPE reports. No signup needed.

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Crypto & SEPA Payment QR Codes: BIP-21, EIP-681 & Security Risks

Explore technical standards for crypto and fiat payment QR codes, including BIP-21, EPC069-12, and critical security risks like QR substitution attacks.

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Click Tracking Without Third-Party Services: UTM Parameters & Static QR Codes

Learn how to implement effective click tracking using static QR codes and UTM parameters in Matomo or Google Analytics, avoiding third-party redirection services.

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Dynamic Page QR Code: Free Alternative to Paid Dynamic Codes

Learn how to create a dynamic page equivalent for your static QR codes using free hosting and redirects, avoiding paid subscriptions and data collection.

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