Glossary Term

Wi-Fi QR Code

glossary wifi qr code featured

A Wi-Fi QR code is a QR code that stores a wireless network’s name, password, and security type, so a phone can join the network after one scan. The credentials sit inside the code as plain text, with no link or server involved. It replaces reading a password off a card and typing it in by hand.

How a Wi-Fi QR Code Works

A Wi-Fi QR code contains a short text string that starts with WIFI:. The phone’s camera recognizes that prefix and offers to join the network instead of opening a web page.

A typical payload looks like this:

WIFI:T:WPA;S:CafeGuest;P:brew2026;;

The format began in the open-source ZXing barcode project, which modeled it on the MeCard contact format. The Wi-Fi Alliance later defined it in section 7 of the WPA3 specification. It is registered with IANA as the provisional wifi URI scheme (2020), described as “a common format for provisioning credentials in a Quick Response (QR) code.”

Wi-Fi QR Code Fields

Each field is a letter, a colon, a value, and a semicolon. Order does not matter, and the string ends with two semicolons.

Field Meaning Example
T Security type: WPA, WEP, or nopass for an open network T:WPA
S Network name (SSID), up to 32 bytes S:CafeGuest
P Password; WPA passphrases are 8 to 63 characters P:brew2026
H true if the network is hidden; omit otherwise H:true

T:WPA covers WPA, WPA2, and most WPA3 networks. The WPA3 specification adds optional fields for newer features, such as transition disable, which most generators do not write.

How Password Length Changes the Code

Longer names and passwords make a Wi-Fi QR code denser. A reproducible test built each payload with Segno 1.6.6 and decoded it with zxing-cpp 3.1.1. Every code decoded back to the exact original text.

Payload Characters QR version (level M / H) Module size at 2.5 cm (M / H)
Open network, no password 27 3 / 4 0.86 mm / 0.76 mm
8-character password 35 3 / 5 0.86 mm / 0.68 mm
16-character password 43 4 / 5 0.76 mm / 0.68 mm
32-character SSID, 24-character password 74 5 / 8 0.68 mm / 0.51 mm
63-character password (maximum) 88 6 / 9 0.61 mm / 0.47 mm

Even the longest WPA password fits in a low QR code version. Size only becomes a problem at level H on very small prints. For a code under 3 cm wide, keep the SSID short.

Special Characters and Escaping

Five characters are reserved in the format: backslash, semicolon, comma, double quote, and colon. Each one must be escaped with a backslash when it appears in a network name or password.

Password:  pa;ss,wo:rd
Correct:   WIFI:T:WPA;S:CafeGuest;P:pa\;ss\,wo\:rd;;
Broken:    WIFI:T:WPA;S:CafeGuest;P:pa;ss,wo:rd;;

In the broken version, a parser that splits on semicolons reads the password as pa. The code still scans, but the phone fails to join. This is the most common reason a Wi-Fi QR code “doesn’t work.” Good generators escape these characters automatically. Hand-built payloads often do not.

Wi-Fi QR Code Security

A Wi-Fi QR code is not encrypted. Any QR scanner app, or a photo of the code, reveals the password as readable text. Treat a printed code the same as a printed password.

Every Wi-Fi QR code is a static QR code, because the credentials are written into the pattern. Changing the password makes the old code useless. Scans also cannot be counted, since no link or redirect is involved.

Frequently Asked Questions

How do you connect to WiFi with a QR code?

Open the phone’s camera, point it at the code, and tap the join prompt that appears. iPhones have read Wi-Fi codes in the Camera app since iOS 11. Android phones read them in the camera or with Google Lens. No separate app is needed.

How do you share Wi-Fi as a QR code from a phone?

Both major platforms can generate one without a third-party app. On iOS 18 and later, open the Passwords app, tap Wi-Fi, select the network, and tap Show Network QR Code. On Android 10 and later, open the network in Wi-Fi settings and tap Share, then confirm with a PIN or fingerprint. Menu names vary slightly by phone maker.

Can someone see the Wi-Fi password in a QR code?

Yes. The password is stored as plain text, so any scanner app that shows raw content displays it. Some Android share screens also print the password under the code. Put Wi-Fi codes only on networks you are willing to share, ideally a separate guest network.

Can a Wi-Fi QR code track scans?

No. A Wi-Fi QR code connects the phone directly to the network, so no server sees the scan. To measure engagement at a venue, add a second code that points to a tracked short link, such as a menu or a feedback page.

To make one with every special character escaped, use the free Wi-Fi QR code generator and test it on an iPhone and an Android phone before printing.

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