Notes from building qr-cow.
Bugs that bit me, things I learned shipping QR codes to 60+ countries, the occasional growth post. Written by hand — no content factory.
QR code versions, explained — and what version your code will be
Every QR code is one of forty sizes, from a tidy 21×21 to a wall-sized 177×177. The version is set automatically by what you encode and how much error correction you want. Here's how to read it, and how to keep yours small.
How to put a logo on a QR code without breaking it
A logo in the middle of a QR code does two things at once. It signals 'this is ours' and it wipes out a chunk of the pattern. Here is the trick.
Five rules for QR codes that actually get scanned
Contrast, quiet zones, size, placement, a real reason to scan. Get these five right and the scan rate roughly doubles.
Static vs dynamic QR codes: pick the right one
Static codes are simple and bulletproof. Dynamic codes change destination and count every scan. Here is when each one wins.
Welcome to the qr-cow blog 🐮
A quick tour of what we will be posting here. Mostly practical guides on getting QR codes scanned, a bit of news, and the odd note from behind the scenes.
What QR code analytics actually tell you
A scan counter on its own is decoration. The interesting question is who scanned, from where, and when. Each answer is an action.
Are QR codes dead in 2026? Not even close
Every few months someone declares QR codes dead, then walks straight into a café and scans the menu. Here is what the data actually shows.
vCard QR codes are eating paper business cards
Most paper business cards end up in a drawer or a bin. A vCard QR drops your contact straight into a phone with two taps. Worth doing.
How to make a Wi-Fi QR code in 30 seconds
Stop reading your password out loud. A Wi-Fi QR code lets people join your network with one scan. Here is how I make mine.