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QRnook

QR code guides

Clear answers to the practical questions that come up before and after a QR code goes to print.

  1. 7 min read

    What is a QR code? How it works, in plain words

    Modules, finder patterns, versions and error correction — what a QR code actually is and why phones can read it so reliably.

  2. 6 min read

    Do QR codes expire? Static vs dynamic codes explained

    A static QR code never stops working on its own. Here is what can break it, how dynamic codes differ, and how to tell which one you have.

  3. 6 min read

    How small can a QR code be?

    The real limits on QR code size: module size, data density, print quality and scanning distance — with practical minimums.

  4. 8 min read

    QR code size for printing: a practical chart

    How big to print a QR code for business cards, flyers, menus, posters and signs, based on scanning distance and how much data it holds.

  5. 7 min read

    QR code error correction (L, M, Q, H) explained

    What the four error-correction levels do, what they cost in size, and which one to pick for print, screens and codes with logos.

  6. 7 min read

    How to create a Wi-Fi QR code that works on every phone

    Step by step: find your exact network name and security type, create the code, and avoid the mistakes that stop guests from joining.

  7. 7 min read

    How to create a Google review QR code

    Get your review link or Place ID, turn it into a QR code, and place it where customers actually scan — within Google’s review rules.

  8. 5 min read

    SVG vs PNG for QR codes: which should you use?

    Vector or pixels? When SVG is the right file for print, when PNG is fine, and how to export a PNG that prints at the right size.

  9. 7 min read

    QR code safety: how to spot a malicious code

    Fake parking stickers, phishing links and app installs: how QR scams work, the warning signs, and how to check a code before you open it.

  10. 6 min read

    QR codes on business cards: size, content and placement

    What to put in a business-card QR code, how small it can be on an 85 × 55 mm card, and print details that make it scan first time.

  11. 8 min read

    Why won’t my QR code scan? Causes and fixes

    A troubleshooting checklist: contrast, quiet zone, size, blur, glare, inverted colours, logos and broken links — and how to fix each.

  12. 5 min read

    The QR code quiet zone: why the empty margin matters

    What the quiet zone is, why the standard asks for four modules, and how designers accidentally remove it when placing codes.

  13. 6 min read

    Can QR codes be coloured? Contrast rules that keep them scannable

    Which colour combinations scan, why light-on-dark is risky, and how to use brand colours without breaking the code.