Articles
Guides, updates, and notes from the QRDock team.
Data Matrix Codes: The Tiny 2D Format on Chips and Medicine
July 15, 2026
Data Matrix codes look like a cousin of the QR code, but they're built for a different job: fitting on a microchip and carrying a drug's full serial history in one scan. Here's what's actually in the square.
How QR Code Login Works — and Why It Can Be Hijacked
July 14, 2026
Scan-to-sign-in is everywhere now — WhatsApp Web, streaming apps, AI chat tools. Here's the mechanism behind QR code login, how attackers exploit the trust it relies on, and the habits that keep your sessions yours.
Do QR Codes Expire? Static, Dynamic, and the Subscription Trap
July 13, 2026
A QR code printed on a business card can outlive the company that made it — or die in a week, depending on which type it is. Here's the difference between static and dynamic QR codes, and why the 'dynamic' kind comes with a subscription you can't afford to forget about.
How to Scan a QR Code From a Screenshot or Saved Photo
July 12, 2026
Camera apps only scan QR codes live — they won't read one sitting in a screenshot or saved photo. This guide covers the built-in workaround on iPhone (Photos > Utilities) and Android (Google Lens), plus why the limitation exists at all and the quickest fix on QRDock.
Static vs. Dynamic QR Codes: What's the Difference?
July 11, 2026
A static QR code carries its destination for life — nothing to update, nothing to break. A dynamic one routes through a server you control, so you can change where it points and see who scanned it. Here's the actual mechanism behind each, and which one fits your use case.
A Brief History of the QR Code: From a 1994 Toyota Parts Plant to Your Pocket
July 10, 2026
In 1994, a Denso Wave engineer named Masahiro Hara solved a boring inventory problem for a Toyota Group supplier — and accidentally invented one of the most-used pieces of visual technology on the planet. Here's how a factory-floor fix became the square you scan for menus, Wi-Fi, and boarding passes.
How to Add a Logo to a QR Code Without Breaking the Scan
July 9, 2026
Dropping a logo into a QR code is easy to get wrong — the scanner treats the logo the same way it treats a smudge or a tear. This is the error correction level, size limit, and placement that actually keep a branded code scanning reliably.
QR Codes for Event Check-In: A Practical Guide for Organizers
July 8, 2026
A per-attendee QR code at the door does more than confirm a ticket — it can log arrivals in real time, stop duplicate entries, and double as a badge that shares your contact card, the venue Wi-Fi, and the next session's calendar invite.
How Much Data Can You Fit in a QR Code? Versions 1-40 Explained
July 7, 2026
A QR code's capacity isn't one fixed number — it depends on version, error correction level, and character type. Here's what actually determines how much a QR code can hold, from 25 characters to nearly 7,000.
How to Create a QR Code That Opens a Specific App (Deep Links Made Simple)
July 6, 2026
A QR code that jumps straight into an app isn't a special format — it's a normal QR code pointing at a verified Universal Link or App Link. Here's how the handoff works, how to set it up, and how to test it before you print.
QR Codes on Product Packaging: What the Brands Are Actually Doing
July 4, 2026
The QR code creeping onto more cereal boxes and snack wrappers isn't just a marketing add-on anymore. Under a standard called GS1 Digital Link, it's the same code a cashier scans at checkout — now also carrying ingredient lists, allergen info, and sustainability details for anyone who points a phone at it.
Why a QR Code Won't Scan: A Five-Minute Troubleshooting Checklist
July 3, 2026
If a QR code refuses to scan, the cause is almost always fixable in under five minutes — bad lighting, the wrong distance or angle, a smudged lens, a too-narrow quiet zone, or damage beyond the code's error correction budget. Here's the checklist to work through, in order.
QR Codes in Healthcare: Patient Wristbands, Medication Tracking, and Privacy
July 2, 2026
The QR code on your hospital wristband and the one on a medical-alert bracelet do real safety work — catching wrong-patient and wrong-dose errors before they happen. Here's how the scanning actually works, where you'll run into it, and what determines who can see the health data behind the code.
Your Phone Can Read More Than QR Codes — A Quick Tour of Ten Barcode Formats
July 1, 2026
Your phone's camera is a general-purpose barcode reader, not just a QR scanner. Here's a quick tour of the ten-plus 1D and 2D barcode formats it can read — from the EAN-13 on your groceries to the PDF417 on your driver's license — and where each one shows up in daily life.
QR Code Marketing in 2026: What's Actually Working (and What Isn't)
June 30, 2026
QR codes are no longer a pandemic novelty — they're a measurable channel. Here's what's working in 2026: dynamic, editable codes with scan tracking and a genuine payoff, plus the vanity codes and broken trust that quietly kill campaigns.
How to Create a QR Code That Pre-Fills a Text or Email
June 29, 2026
Make a QR code that opens Messages or email with the recipient and message already typed. Build the sms: or mailto: link, encode the text, and test it.
iPhone vs. Android QR Scanner: What's Built-In and What's Not
June 27, 2026
Both iPhone and Android scan QR codes from the built-in camera, no app needed. Here's how each one works, why they differ, and what the native scanners leave out.
How to Print a QR Code So It Actually Scans
June 24, 2026
A QR code that looks perfect on screen can fail completely once it's on paper. Four things decide whether a printed code scans: how big it is, the blank quiet zone around it, how cleanly each module prints, and the contrast between the code and its background. Get those right and almost any phone reads it on the first try.
Aztec Codes: The Square-Spiral Format on Your Train and Concert Tickets
June 18, 2026
The square barcode with a bullseye on your train ticket or concert pass is an Aztec Code, not a QR code. Here's how it works and why transit loves it.
PDF417 vs. QR Code: Why Boarding Passes and IDs Use a Different Barcode
June 15, 2026
The long rectangle on your boarding pass or driver's license is a PDF417 barcode, not a QR code. Here's why those documents use it and what your phone can read.
How to Make a Calendar Event QR Code That Adds the Event in One Tap
June 9, 2026
A calendar event QR code holds an iCalendar event, so one scan adds the date, time, and location to your guest's calendar. Here's how to make one.
QR Codes for Small Business: A Plain-English Guide for Owners
June 6, 2026
A plain-English guide to QR codes for small business: menus, guest Wi-Fi, vCards, Google reviews, payments, plus static vs. dynamic and sticker-scam safety.
How to Spot a Fake QR Code on a Parking Meter
June 3, 2026
Sticker scams on parking meters are spreading from Austin to Los Angeles. Drivers scan, pay, and the money never reaches the city. The tells are quick — peeling edges, look-alike URLs, no zone number — and most fakes give themselves away before you tap. Here's the four-point check, plus what to do if you already scanned.
QR Code Error Correction: How Logos and Damage Don't Break the Scan
May 30, 2026
QR code error correction is the built-in math that recovers your data when part of the symbol is smudged, scratched, or covered by a logo. Here is how the four levels — L, M, Q, H — actually work, and which one to pick.
How to Generate a Payment QR Code for Apple Wallet, Venmo, or PayPal
May 27, 2026
The payment QR code you need usually already exists inside Venmo, PayPal, or an Apple Wallet pass — you just have to know where to look. This guide walks through all three, plus how to print one that won't get sticker-swapped.
QR Code Menus: Are They Going Away or Here to Stay?
May 21, 2026
QR code menus exploded during the pandemic, then ran into a backlash. At sit-down restaurants diners want paper back; at cafes and fast-casual spots the codes are holding on. Here's what the surveys actually show, where QR menus still earn their place, and the hybrid setup most restaurants are landing on — plus what to do if you keep one.
How to Make a vCard QR Code That Saves Contact Info in One Tap
May 18, 2026
Build a vCard QR code that scans cleanly on iPhone and Android. Field choices, vCard 3.0 vs 4.0, error correction, and testing — all in 850 words.
QR Code vs. Barcode — When to Use Which (and What Your Phone Can Read)
May 17, 2026
QR codes are barcodes — specifically, two-dimensional ones. This is the practical difference between the striped retail barcode on a soup can and the square code on a menu, including how much data each holds, what your phone can read out of the box, and when to pick which format.
Quishing Explained: Why QR Code Phishing Doubled in the Last Year
May 15, 2026
Quishing is phishing dressed up as a QR code. Cases roughly doubled in the last year because the QR image bypasses email filters, lands the victim on a personal phone outside corporate defenses, and now shows up in state-actor playbooks. Here is what it is and how to spot it before you tap.
How to Create a Wi-Fi QR Code So Guests Connect Without Typing the Password
May 12, 2026
Typing Buffalo7$Caterpillar! into a guest's phone is a small kind of cruelty. A Wi-Fi QR code skips that. Here's the format, how to make one, and where it works.
Is It Safe to Scan a QR Code? Quishing, Sticker Scams, and How to Stay Safe
May 10, 2026
Scanning a QR code is as safe as the URL it points to — no more, no less. Quishing (QR-code phishing) and physical sticker overlays on parking meters, menus, and packages are the two patterns to watch for. Here's how to spot both, and what to do if you already scanned a bad one.
How QR Codes Actually Work — Finder Patterns, Modules, and Error Correction
May 6, 2026
What's inside a QR code — the grid of modules, the three corner finder squares, and the Reed–Solomon error correction that lets a smudged code still scan.
What the Three Squares in a QR Code Actually Do (Finder Patterns Explained)
The three big squares in the corners of a QR code are called finder patterns. They are the reason your phone can detect a code in a fraction of a second, at any angle, even when part of the code is scratched or covered by a logo. Here is what each square actually does and the 1:1:3:1:1 ratio behind them.