Guest Wi-Fi QR — Settings and quality

Worked example

Pick WPA / WPA2 unless the router is open or WEP, keep error correction at H or M, and export 1440 px or SVG for table cards.

For a Wi-Fi code the settings that matter are security type, hidden flag, error correction and size, in that order. Choosing WPA / WPA2 writes T:WPA into the string; Open network writes T:nopass and drops the password field; WEP writes T:WEP. Pick the one the router uses, because a mismatch is the single most common reason a join fails.

The example string WIFI:T:WPA;S:Guest;P:example-only;; is about 35 characters, which fits a code of roughly 29 by 29 modules at level M and 37 by 37 at level H. A longer SSID and a 24-character password push a code up toward 41 by 41 modules. Tool defaults start at H, the highest level, which suits a laminated card in a busy cafe; M is fine for a small card on a clean wall, giving larger squares at the same print size.

The tool escapes the characters backslash, semicolon, comma and colon in the name and password so they are not read as separators. You do not need to type those escapes yourself, and doing so would double them. A password such as tea;time:2 therefore works as typed, but fully check it on a phone afterward because some older readers handle escapes less well.

Size and border: export at 720 px for a screen or a menu board, and use an SVG or 1440 px PNG for a printed table card of 3 to 4 cm. Keep the quiet border at 18 px or more. The default center mark is the Chatcument logo; for a hospitality card you can replace it with your own image (12 to 32 percent of the width), but a logo is only safe at level H.

The trade-off is between a short, easy password and a safer one. A 10-character guest password produces a smaller, easier-to-scan code than a 30-character one, and since the code is public anyway, rotating a modest password regularly beats printing a long one forever.

Guest network; example-only password

WIFI:T:WPA;S:Guest;P:example-only;;

Security type must match the router; the password is escaped automatically and stored readably in the code.