How Do QR Codes Work? A Plain-English Explanation
The corner squares, the random-looking speckle, the blank margin — every part of a QR code is doing a specific job. Here is what each one does, and why that matters when you print one.
6 min readMake a QR code for a link, your Wi-Fi, a contact card, WhatsApp and more. Download print-ready PNG or SVG straight away—no sign-up, no watermark, and nothing expires. Everything is generated in your browser, so what you type never leaves your device.
Free to use, including commercially. No watermark, no sign-up.
Each type encodes a different format, so pick the one that matches what you want to happen when someone scans.
Paste a web address and get a QR code that opens it when scanned. Download it as a PNG for slides and social, or as an SVG your printer can scale to any size without it going soft.
Encode a message that simply appears on screen when someone scans it. Nothing opens and nothing loads, so a text code works even where there is no signal at all.
Let guests join your network by scanning instead of typing a password wrong three times. Works on iPhone and Android cameras with nothing to install.
Encode your contact details so one scan opens a pre-filled contact card ready to save. No app required, and it works offline because the details live in the pattern.
Open a scanner's mail app with the address, subject, and body already written. It removes the two things that stop people emailing you: finding the address and working out what to say.
Open the messaging app with your number and a pre-written text already in place. Useful for keyword campaigns and any flow where a reply needs to arrive from the customer's own number.
Scanning brings up your number in the dialler, ready to call. It suits situations where someone needs to reach you immediately and cannot type a number — driving, carrying something, or standing in the rain.
Open a WhatsApp chat with your business, message already written. For a lot of customers WhatsApp is where buying actually happens, and this removes the step where they have to find you first.
Encode a latitude and longitude so scanning opens the spot in the phone's map app. It is the reliable way to point people at somewhere a street address describes badly.
Encode an event so scanning offers to add it to the calendar with the date, time, and venue already filled in. It closes the gap between someone seeing your poster and actually remembering to turn up.
Yes. Every type here is free to make and free to use commercially, with no watermark, no sign-up, and no limit on how many you create. The codes never expire because there is nothing on our side for them to depend on.
No. These are static codes, meaning the destination is encoded directly into the pattern. There is no redirect and no account behind them, so they keep working for as long as whatever they point at exists.
A static code has its destination baked into the pattern, so it can never be changed or counted. A dynamic code points at a short redirect you control, so you can change where it goes after it is printed and see every scan. Static codes suit fixed information like a Wi-Fi password; dynamic codes suit anything you are spending money to promote.
SVG for anything going to print. It is a vector, so a printer can scale it to a billboard without the edges going soft. PNG is fine for screens, slides and social posts.
About 2cm square is the practical floor for a code someone scans up close, and you want more for anything read at a distance. Denser codes need more room, so shortening the encoded text lets you print smaller.
No. The codes are generated entirely in your browser, so what you type—including Wi-Fi passwords and contact details—never leaves your device.
Static codes are fixed forever. Dynamic codes keep the same printed pattern but let you change where they point and show you every scan—when, where, and on what device.
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The corner squares, the random-looking speckle, the blank margin — every part of a QR code is doing a specific job. Here is what each one does, and why that matters when you print one.
6 min readA logo in the middle of a code is not a trick or a hack. It works because QR codes carry redundant data. The question is how much of that redundancy you can spend before the code stops scanning.
5 min readA QR code is just text — it cannot infect anything. The risk lives entirely in where it sends you, and in whether somebody has stuck a different code over yours.
6 min read