How to Make a WiFi QR Code (and How It Works)

A WiFi QR code is an ordinary QR code that holds one line of text in this shape:

WIFI:T:WPA;S:<network>;P:<password>;H:true;;

Fields can appear in any order. Each ends with a semicolon, and the whole string ends with one more, which is why it finishes with ;;. These rules come from the ZXing project’s Barcode Contents wiki (checked October 2026). ZXing, the open-source barcode library, proposed the format there, modeling it on the MECARD contact format.

It has since been formalized. The IANA registration of the wifi URI scheme (provisional, registered August 2020) points to section 7 of the Wi-Fi Alliance’s WPA3 specification as the format’s formal definition.

When a phone’s camera recognizes the WIFI: prefix, it offers to join the network. No web page or server is involved, which makes a WiFi code static by nature.

The format uses semicolons to separate fields and a colon after each field letter, so those characters inside a name or password would confuse the reader. The ZXing wiki says to put a backslash in front of each of these:

For example, the password pa;ss:word goes into the code as:

WIFI:T:WPA;S:Cafe Guest;P:pa\;ss\:word;;

The same wiki adds one oddity: a network name made only of hexadecimal characters, such as CAFE or 1234, could be read as hex, and it suggests wrapping such a name in double quotes.

Match the setting on your router:

• WPA2 or WPA3 with a password (“Personal”): use T:WPA. Router menus may say WPA2-PSK, WPA2/WPA3 or WPA3-Personal; the code normally says WPA for all of them. Some phones write T:SAE for WPA3-only networks instead: Android’s own share-network feature defines that value in its open-source Settings code (checked October 2026). Either way, test with both an iPhone and an Android phone.
• WEP: use T:WEP. WEP is an old, broken standard; if your router still offers it, switch to WPA2 or WPA3.
• Open network: use T:nopass and leave out the password.
• Enterprise (802.1X/EAP), where each person signs in with their own username: the ZXing wiki describes extra fields for this, but phone support varies, so test carefully. Printing personal credentials is rarely wise anyway; a guest network is usually the better answer.

1. Set up a guest network. Give it its own password, separate from the network your payment terminal, cameras and computers use.
2. Write down the exact name and password. Both are case-sensitive, and spaces count.
3. Enter them in a WiFi QR generator. Pick the security type and tick “hidden” only if the network doesn’t broadcast its name.
4. Download a print format. SVG stays sharp at any size; PNG is fine for screens and small prints.
5. Test before printing. Forget the network on an iPhone and an Android phone, then scan from where guests will stand.
6. Print and place it. Add the network name and password in text beside the code.

For step 3 you can use the free WiFi QR code generator. In CirculateQR, WiFi codes are always static and included on the free plan, which has unlimited static codes, and they never expire. Exports come as PNG, SVG or PDF. Because the code never touches a server, there are no scan counts. Details are on the pricing page.

A café runs a WPA2 guest network called “Cafe Guest” with the password “espresso-2026”. The code holds:

WIFI:T:WPA;S:Cafe Guest;P:espresso-2026;;

That is 41 characters, which fits a version 3 code, 29 × 29 modules, at error correction level M. Adding H:true for a hidden network makes it 48 characters and version 4, 33 × 33, so only add it when the network really is hidden.

For size, a common rule of thumb is a code width of one tenth of the scanning distance. A card on the counter, scanned from about 30 cm, needs a code about 3 cm (1.2 in) wide. Each module is then about 1 mm, and with the 4-module quiet zone the code needs a clear square of about 3.8 cm. A wall sign read from 1.5 m needs a code about 15 cm wide. CirculateQR draws plain codes at level H, so the same text becomes version 5, 37 × 37; at 3 cm each module is about 0.8 mm, still comfortable. The size guide and error correction guide explain the trade-off.

It is exactly as safe as writing the password on a sign, because that is what it is. A QR reader app can show the full contents, password included, and anyone who photographs the code can join later from the parking lot.

• Use a guest network. It keeps visitors off the network your payment terminal, cameras and office computers use.
• Change the guest password only as often as you can reprint. Every change means new codes, so use cheap cards or stickers rather than a window decal.
• Keep codes out of view from the street if you don’t want passers-by on your connection.
• Check your codes now and then. A sticker with a different WiFi code could send guests to someone else’s hotspot. See QR code security.

Put it where people sit down and reach for their phone:

• Café and restaurant tables, on a table tent or the menu card
• The counter or reception desk, at eye level, away from glare
• Hotel rooms and vacation rentals, on the desk card or in the welcome book
• Waiting rooms, meeting rooms and coworking desks

Always print the network name and password as text next to the code. Laptops can’t easily scan it, and a guest whose phone won’t read it can still type. A short label such as “Scan to join our WiFi” tells people what the code does before they point a camera at it.