How to make a Wi-Fi QR code that actually connects

6 minute read · updated 2026-10-19

A Wi-Fi QR code saves your guests from squinting at a password written on a till receipt. Point a phone camera at it, tap the prompt, and the phone joins the network. No typing, no spelling out whether that character is a one or a lowercase L.

It works because the code does not hold a link. It holds a short piece of structured text that phones recognise as network credentials. Get one detail wrong and it fails silently, which is why it is worth knowing what goes into it.

What is actually inside the code

The payload is a single line of text that looks roughly like this: WIFI:T:WPA;S:NetworkName;P:ThePassword;;

Four things matter.

The network name (SSID) — exactly as it is broadcast, character for character.
The security type — WPA covers WPA, WPA2 and WPA3 for the purposes of this code. WEP is a separate, obsolete setting. An open network with no password uses the "nopass" type and no password field.
The password — omitted entirely on an open network.
The hidden flag — set this only if your router is configured not to broadcast its name. Setting it on a visible network can stop the join from working on some phones, so leave it off unless you know the network is hidden.

If you build the code with a tool like Codeshed, you just fill in those fields and the payload is assembled for you. It is still useful to know the shape of it, because almost every failure traces back to one of those four values.

Capital letters count

SSIDs are case-sensitive. Cafe Guest and cafe guest are two different networks as far as the phone is concerned, and it will not quietly correct you. Passwords are case-sensitive too.

Copy both from the router's admin page or the label on the back of the router, rather than from memory. If the name contains a trailing space, which happens more often than you would think, that space is part of the name.

Awkward characters in passwords

The payload uses the semicolon as a separator and the colon as a field marker. So if your password contains a semicolon, a colon, a comma, a backslash or a double quote, those characters have to be escaped with a backslash, or the phone reads your password as the end of one field and the start of another. A password of sun;shine becomes sun\;shine inside the code.

Spaces are fine in themselves and need no escaping, but they cause a different problem: nobody can tell from looking at a printed password whether there is one space or two. The QR code removes that ambiguity, which is one of the better reasons to use one.

Any decent generator handles the escaping for you. Codeshed does it in the browser as you type, and nothing you enter leaves your device. Still, the simplest fix is a password that avoids punctuation altogether.

iPhone and Android

Both handle this natively. iPhones have read Wi-Fi QR codes from the built-in Camera app since iOS 11, and Android since version 10, with many manufacturers supporting it earlier through their own camera apps. The phone shows a prompt such as "Join network" and the user taps it.

The behaviour differs slightly. iPhones tend to join immediately on tapping. Android sometimes opens the Wi-Fi settings screen with the network pre-filled, which confuses people who expect to be connected already. Neither is broken. If you are putting a code on a wall, a line of text underneath saying "scan with your camera to join" prevents most of the confusion.

Very old phones, and some locked-down work devices, will read the code as meaningless text. Always print the network name and password alongside the code as a fallback. The code is a convenience, not a replacement.

Share the guest network, not the main one

In a cafe, a holiday let or an office reception, put your guest network on the code. Most routers made in the last decade can run one. A guest network gives internet access while keeping visitors off the same network as your till, your printer, your cameras and your own laptops.

It also means a password on a wall is not a password that unlocks anything else. If the code is photographed and shared, which it will be, the worst case is somebody using your broadband from the pavement outside.

When the password changes

The password is baked into the image. Change it on the router and every printed code becomes a dead end. There is no way to update a Wi-Fi QR code remotely, because the phone never contacts a server, it just reads text.

So plan for it. Keep the original file, note the date, and reprint when you rotate the password. If you rotate often, print the code small and cheap rather than having it engraved.

Where to put it

Head height on a wall, or on a table tent, works best. Phones need a moment to focus, so a code behind glass at an angle or stuck to a dark surface at knee level will frustrate people. Allow a clear white border around the code, and keep it large enough for the distance people will scan from — see how big should a QR code be for the sizing rule of thumb.

Before you print a batch, test the code with at least two phones, ideally one iPhone and one Android, and with the network password you are actually going to use.