Reading a Wi-Fi password aloud — "capital S, then dollar, no, the other dollar" — is a small, universal irritation. A Wi-Fi QR code removes it: the guest points a camera, taps once, and is connected.
How it works
A Wi-Fi QR code is not magic and it is not a link. It contains a short line of plain text in a format phones understand:
WIFI:T:WPA;S:MyNetwork;P:MyPassword;;
- T — security type: WPA (covers WPA2 and WPA3), WEP, or nopass for an open network
- S — the network name, exactly as it appears, case-sensitive
- P — the password
- H — add
H:trueif the network is hidden
Both Android and iOS have recognised this format for years. The camera app reads it and offers to join the network.
Making one
- Open the QR code generator and choose Wi-Fi
- Enter the network name exactly — Home_5G and home_5g are different networks
- Enter the password and pick the security type (WPA covers almost everything modern)
- Download as PNG for printing, or SVG if you want to resize it without blurring
The code is generated inside your browser. Your Wi-Fi password never leaves your device, which matters rather a lot for this particular use — a generator that sends your password to a server is a bad idea regardless of what its privacy policy says.
Where to put it
- Homes: printed on a card by the door or on the fridge, so guests never ask
- Cafés and restaurants: on the table tent or the back of the menu
- Offices: in the reception area, pointing at the guest network — never the internal one
- Rentals and guest houses: in the welcome folder, saving a message at eleven at night
- Events: on the badge or the programme
Practical notes on printing
Size. Roughly 2 × 2 cm printed is the minimum for reliable scanning at arm's length. If it will be read from across a room, scale up — a rough guide is one centimetre of code for every ten centimetres of distance.
Contrast. Dark code on a light background. Inverted codes fail on many scanners, and low-contrast pastel combinations fail on most.
Quiet zone. Leave clear white space around the code, roughly the width of four modules. Text or a border crowding the edge breaks the scan.
Error correction. Higher levels let the code survive smudges and scratches, at the cost of a denser pattern. For a card that will be handled daily, choose a higher level; for a clean printed sheet, medium is fine.
Test before printing a hundred. Scan it with an Android phone and an iPhone. It takes a minute and it has saved many people a reprint.
Security, honestly
A QR code does not hide your password. Anyone who scans it gets the network credentials, exactly as if you had read them aloud — and someone can photograph the code from across a room and read it later.
What to do about that depends on the setting:
- At home, it is fine. Anyone in your hallway could have asked anyway.
- In a business, put the code on the guest network only. Guest networks isolate clients from each other and from your internal machines, which is the whole point of having one.
- In a shop window or anywhere public, do not print the code for a network you care about. Use a guest network with a password you rotate.
Other things worth a QR code
The same generator handles several formats that save more typing than a URL does:
- UPI payment — amount and note pre-filled, so the payer only confirms
- Contact card (vCard) — name, phone, email saved in one tap, useful on a business card
- SMS or WhatsApp — opens a chat with your message already written
- Location — opens map coordinates, better than an address for a venue that is hard to find
- Plain text — a serial number, a wing and flat number, a machine ID
One caution that applies to all of them: a printed QR code cannot be changed. If the underlying detail might change — a phone number, a URL, a Wi-Fi password you rotate — either accept that you will reprint, or point the code at something stable like a short link you control.