How to make a Wi-Fi QR code guests can scan to connect

A Wi-Fi QR code is a QR code containing a short line of text in a standard format — WIFI:T:WPA;S:NetworkName;P:password;; — that the camera apps on iOS and Android recognise. Point a phone at it and the phone offers to join the network. There is nothing to install and nothing to sign up for, because the whole thing is that one line of text encoded as a picture.

The quickest route here: open the QR Code Generator, set Content type to Wi-Fi, type the Network name (SSID) exactly as it appears, enter the Password, pick the Security type, and download the PNG or SVG. The code is built in your browser, so the password is never sent anywhere; it is also static, which means it never expires and never stops working because a service shut down.

Three ways to get one

Method	Good for	Watch out for
A generator like this one	A printed card for guests; any network whose password you know	You have to type the SSID exactly right
Android's built-in sharing	Sharing the network you are already on, phone to phone	Only for a network the phone has joined
iPhone (iOS 18 and later)	The same, from an iPhone, including to Android users	Older iOS versions have no QR option

Android. Open Settings → Network & internet → Internet, tap your Wi-Fi network, then tap Share. After you confirm with your fingerprint or PIN, the phone displays a QR code for that network. Anyone can scan it, including iPhone users. This has been available since Android 10.

iPhone. Two different features get confused. The first is proximity sharing: when another Apple device that has your Apple Account email in its Contacts tries to join a network you are on, a Share Password prompt appears on your screen. Both devices must be unlocked and nearby with Wi-Fi and Bluetooth on, and it does not work with Android. The second, from iOS 18 onwards, is a real QR code: open the Passwords app, go to Wi-Fi, tap the network, and choose Show Network QR Code. Any phone can scan that one.

Use a generator when you want a code on paper — a card by the door, a sign in a café — or when the password lives in the router's admin page and not on any phone.

What is actually inside the code

The payload is plain text:

WIFI:T:WPA;S:Cafe-Lumiere;P:correct-horse-battery;;

T is the security type (WPA covers WPA, WPA2 and WPA3; WEP; or nopass for an open network), S is the network name and P is the password. Characters that would otherwise end a field — ; , : " — are escaped with a backslash. The format is public and unencrypted: anyone who scans the picture can read the password out of it, so a Wi-Fi QR code is a convenience, not a secret.

Printing it so it scans first time

A QR code is a grid of squares called modules. The 51-character example above needs 29 × 29 modules at Low error correction, 33 × 33 at Medium, 37 × 37 at Quartile and 41 × 41 at High. Printed 3 cm wide, a 33 × 33 code gives modules about 0.9 mm across — comfortable for a phone camera at arm's length — while the 41 × 41 version drops to roughly 0.7 mm.

• Print at least 3 × 3 cm, and larger for a code on a wall people will scan from a metre away.
• Keep it dark on light. Black on white is the safest. Inverted codes and low-contrast colour pairs fail on some scanners.
• Leave white space around it. The specification calls for a quiet zone four modules wide on every side; this generator leaves two, so give the code a margin when you place it on a poster or a card.
• Choose High error correction only if the code will be scratched, folded, laminated or partly covered — it recovers about 30% of the code, against 7% at Low, at the cost of a denser grid.
• Add a line of text: "Wi-Fi: Cafe-Lumiere — scan to join". Some people's cameras do not read QR codes, and some will want to type it.
• The download is a PNG for printing at a known size, or an SVG for sharp printing at any size. If your printer or design tool needs a raster file, SVG to PNG converts it at whatever resolution you choose — see JPG, PNG or WebP: which one for why PNG rather than JPG for line art.

Keeping your network safe

• Put guests on the guest network. Most routers can run a separate SSID that has internet access but cannot reach your computers, NAS or smart devices. Make the QR code for that one.
• Anyone who photographs the code has the password. That is fine for a café and not fine for a code taped to a shop window next to the till.
• Do not use WEP. It is broken; if your router still offers only WEP, it is old enough to replace.
• Changing the password invalidates the code. Generate a new password with the Password Generator, update the router, and print a new card.

When the code will not connect

The SSID is not exactly right. Network names are case-sensitive and a trailing space counts. Copy it from the router's admin page rather than retyping it from memory.

The security type is wrong. A code that says WPA for an open network, or nopass for a protected one, produces a failure with no useful message. Match what the router is actually running.

The network is hidden. A hidden SSID needs an extra H:true; field so the phone knows to search for it. This generator does not add that field, so either unhide the network or have guests add it manually.

The password contains a backslash. Backslash is the escape character in this format and is the one case this generator does not escape for you. Change the password, or have guests type it.

It is a captive-portal network. Hotels, airports and some cafés put you on an open network and then require a sign-in page. The QR code joins the radio network correctly; the browser page still appears.

It is an enterprise network. WPA2-Enterprise and WPA3-Enterprise use per-user credentials over 802.1X, which the WIFI: format does not describe. Office networks of this kind need a configuration profile, not a QR code.

The device is 2.4 GHz only. Some smart plugs, printers and older devices cannot see a 5 GHz or 6 GHz band. If your router advertises one SSID across all bands, the code is fine and the device is the problem.

The camera shows the text instead of a Join prompt. The phone read the code but does not know the Wi-Fi format. iOS has understood it since iOS 11 and Android since Android 10; anything older needs a QR scanner app.

Questions people ask

Does the code expire? No. It is a picture of a text string. It stops working only when the network name or password changes.

Is my password sent to a server? No. The code is generated in your browser.

Can someone extract the password from the image? Yes — any QR scanner will display it. Treat a printed code the same way you would treat the password written out in full.

Can I put it on a business card? Yes, at 2 cm it will usually still scan on a matte card. Test with two or three phones before printing a thousand.

What about a barcode instead? A one-dimensional barcode cannot hold this much text. Barcode Generator is for product and inventory codes.

Next steps

• Build the code: QR Code Generator
• Generate a guest-network password worth printing: Password Generator, and the guide How to create a strong password