QR code formats: encoding Wi-Fi, contacts, calendars, and payments

A QR code is a text container

Everything a QR code can do is really about the text inside it. Scanners look at the first few characters and decide how to interpret the payload:

• http:// or https:// → open a URL
• WIFI: → connect to Wi-Fi
• BEGIN:VCARD → save as contact
• BEGIN:VEVENT → add to calendar
• mailto: → compose email
• tel: → dial a phone number
• sms: → open SMS
• geo: → open in a map

Anything else is treated as plain text. Nothing here requires proprietary APIs; every format below is a public standard.

Wi-Fi

The de-facto format, supported by iOS, Android, and every modern camera:

WIFI:T:WPA;S:MyNetwork;P:MyPassword;;

The fields:

• T - auth type: WPA, WEP, or nopass (open network).
• S - SSID (network name).
• P - password (omit for open networks).
• H:true - optional, marks the network as hidden.

Special characters (\, ;, ,, :, ") in the SSID or password must be escaped with a backslash. Trailing ;; is required.

vCard (contacts)

vCard 3.0 is the safest version - every scanner understands it:

BEGIN:VCARD
VERSION:3.0
FN:Ada Lovelace
ORG:Analytical Engines
TEL:+441234567890
EMAIL:ada@example.com
URL:https://example.com
END:VCARD

Keep it short - QR codes have a hard capacity limit (about 2,900 bytes at maximum size with lowest error correction). Long vCards produce dense, unscannable codes.

Calendar events (iCalendar)

BEGIN:VEVENT
SUMMARY:Product Launch
DTSTART:20260901T140000Z
DTEND:20260901T150000Z
LOCATION:HQ Boardroom
DESCRIPTION:Kickoff meeting
END:VEVENT

Dates use the compact ICS format - no dashes, no colons, Z for UTC. Some scanners want the full VCALENDAR wrapper; most accept a bare VEVENT.

URL - the boring but most-scanned format

Just paste the URL. Two tips:

1. Uppercase HTTPS URLs compress better. QR codes have a special "alphanumeric" mode that packs A-Z, 0-9, and a few symbols more densely than the "byte" mode used for mixed-case text. HTTPS://EXAMPLE.COM/PATH produces a smaller, denser code than https://example.com/path. In practice most people don't bother - but for print, where scanning distance matters, it helps.
2. Add UTM parameters if you need to measure QR-driven traffic. The QR itself is untrackable; the URL it encodes isn't.

Payments

Region-specific and evolving:

• UPI (India): upi://pay?pa=merchant@bank&pn=MerchantName&am=100.00&cu=INR
• EMVCo QR (global standard, used by PayNow, PromptPay, etc.): a structured format with tag-length-value fields - usually generated by payment SDKs, not by hand.
• PayPal.me link: just a URL - https://paypal.me/username/25.

Error correction: pick the right level

QR codes reserve some bits for error correction. Four levels:

• L (7%) - smallest code, minimal damage tolerance. Fine for screens.
• M (15%) - default. Handles small print imperfections.
• Q (25%) - for outdoor use, faded labels.
• H (30%) - required if you want to overlay a logo in the center.

Higher levels mean a denser code that stores less data. If your data barely fits at level M, dropping to L helps; if the code needs to survive rain, go H.

Making a QR safely

QR Code Generator runs entirely in your browser - the content you're encoding (Wi-Fi passwords, private URLs, contact details) never touches a server. It downloads as PNG (screens, social) or SVG (print, unlimited scaling).

Related tools:

• URL Encoder - for parameters that need to survive being embedded in the QR's URL.
• Base64 Encoder - for embedding small images in QR-directed vCards.