Calculatormatics

QR Code Generator — Free Text, URL, WiFi & vCard Codes

Generate free QR codes for any purpose — websites, WiFi networks, contact cards, email addresses, phone numbers, and SMS messages. Select your content type, fill in the fields, and your QR code appears instantly. You can download it as a PNG at three sizes (128×128, 256×256, or 512×512 pixels) with four error correction levels so your code remains readable even if partially damaged. QR codes were invented in 1994 by Denso Wave (a Toyota subsidiary) to track automotive parts; today they encode everything from restaurant menus to payment links. This generator supports seven content types: plain text, URL, WiFi, email, phone, SMS, and vCard (contact). QR rendering uses the qrserver.com public API — see the privacy note below. No account required.

Generated QR Code

Size: 256×256px  |  Error correction: M  |  Rendered via qrserver.com

Encoded data:

https://example.com

Privacy notice: QR code images are rendered by the qrserver.com public API. Your QR content is sent to their servers. Do not encode sensitive credentials, private keys, or personal data you would not share with a third party.

Types of QR Code Content

Different content types produce different data strings inside the QR code. Your phone's camera app or QR scanner reads the string and decides what to do with it. Here are the seven types supported by this generator:

Type What it does Example encoded string
URL Opens a web page in the browser https://example.com
Plain Text Displays text on screen Hello, World!
WiFi Offers to join a wireless network WIFI:T:WPA;S:MyNet;P:pass;;
Email Opens email app with pre-filled fields mailto:you@example.com?subject=Hi
Phone Dials or prompts a phone call tel:+14155551234
SMS Opens SMS app with pre-filled number/message smsto:+14155551234:Hello!
vCard Offers to save a contact to the address book BEGIN:VCARD
VERSION:3.0
FN:Jane Smith
...

Error Correction Levels

QR codes use Reed-Solomon error correction to remain scannable even when part of the code is damaged, dirty, or obscured. Four levels are defined in the QR standard:

Level Symbol Recovery capacity Best for
Low L 7% of codewords Digital screens, clean environments
Medium M 15% of codewords General purpose (default)
Quartile Q 25% of codewords Print materials, light wear expected
High H 30% of codewords Stickers, outdoor signage, logos overlaid

Higher error correction produces a more complex QR code with more modules. For the same payload, a Level H code will be slightly denser than a Level L code. If you need to overlay a logo on your QR code, use Level H to ensure the code can still be decoded despite the logo covering some modules.

Worked Example: Encoding Different Data Types

Below are the exact strings encoded for three common use cases. You can paste these into any QR encoder to reproduce the same results.

URL:

https://calculatormatics.com/utilities/qr-code-generator

WiFi (WPA2, SSID "HomeNetwork", password "s3cur3pass"):

WIFI:T:WPA;S:HomeNetwork;P:s3cur3pass;H:;;

vCard (minimal contact):

BEGIN:VCARD
VERSION:3.0
FN:Jane Smith
ORG:Acme Corp
TEL;TYPE=CELL:+14155551234
EMAIL:jane@example.com
URL:https://janesmith.com
END:VCARD

Email with subject and body:

mailto:support@example.com?subject=Help%20request&body=Hello%2C%20I%20need%20help%20with...

How QR Codes Work

A QR code is a two-dimensional grid of dark and light squares called modules. Each module represents one bit of information. The key structural elements are:

Because finder patterns appear in exactly three corners (not four), a scanner can always determine the correct orientation — even when the code is upside down or at an angle. QR codes can be read reliably at angles up to about 30° from perpendicular.

WiFi QR Code Format

The WiFi QR format was standardized by ZXing (Zebra Crossing) and is supported natively by Android 10+ and iOS 11+. The format is:

WIFI:T:<type>;S:<ssid>;P:<password>;H:<hidden>;;

Where:

A real-world example for a network called "Café Wi-Fi" with WPA2 password "coffee:time":

WIFI:T:WPA;S:Caf\u00e9 Wi-Fi;P:coffee\:time;H:;;

The double semicolon ;; at the end is required by the format specification. iOS will show a notification asking if the user wants to join; Android 10+ will show a similar prompt in the camera app.

vCard Format for Contacts

vCard 3.0 is an RFC 2426 standard for exchanging electronic business cards. A minimal valid vCard QR code looks like this:

BEGIN:VCARD
VERSION:3.0
FN:Jane Smith
ORG:Acme Corp
TEL;TYPE=CELL:+14155551234
TEL;TYPE=WORK:+18005550100
EMAIL:jane@example.com
URL:https://janesmith.com
END:VCARD

Key fields:

The BEGIN:VCARD and END:VCARD markers are required. Lines are separated by CRLF (\r\n) per the standard, though most scanners accept LF-only. Both iOS and Android will offer to import the contact when the QR code is scanned.

Privacy Note

QR image rendering in this tool uses the qrserver.com public API maintained by goQR.me. When you click generate, your QR payload is sent to their servers as a URL-encoded query parameter to render the PNG image. This means:

Recommendation: For sensitive data — network passwords you use for a home or corporate network, private keys, internal system URLs, or personally identifiable information — use an offline QR generator instead. For public URLs, public contact details, and generic text, this tool is convenient and safe. The qrserver.com API is a well-established free service but is not end-to-end encrypted for the query parameter.

Frequently Asked Questions

What is a QR code and how does it work?

A QR code (Quick Response code) is a two-dimensional matrix barcode invented in 1994 by Denso Wave, a Toyota subsidiary. It stores data as a pattern of black and white squares (called modules) arranged on a square grid. A camera or scanner captures the pattern and decodes it using the Reed-Solomon error correction algorithm. QR codes can encode URLs, text, binary data, and structured formats such as WiFi credentials and contact cards. Unlike 1D barcodes, a QR code can be read from any angle because of three distinctive "finder patterns" (the square markers in three corners) that let scanners orient themselves.

What is the maximum amount of data a QR code can hold?

QR code capacity depends on data type and error correction level. At the highest version (Version 40, Low error correction), a QR code can store: 7,089 numeric characters, 4,296 alphanumeric characters, 2,953 bytes of binary data, or 1,817 Kanji/Kana characters. Most practical uses (a URL, WiFi credentials, contact card) use much lower versions with far fewer modules, resulting in a simpler and more scannable code. As you increase the error correction level, the code must store more redundancy data, which reduces the payload capacity at any given size.

What error correction level should I use?

Choose based on where the QR code will be displayed. Low (L, 7%) — use for digital screens where no damage is expected; produces the smallest, densest code. Medium (M, 15%) — good general-purpose default; handles minor distortion. Quartile (Q, 25%) — recommended for print materials that may get slightly worn. High (H, 30%) — best for stickers, packaging, or outdoor signage where up to 30% of the code may be obscured or damaged. A higher level means a slightly larger or more complex code. For logos overlaid on QR codes, use H so the code can still be decoded despite the logo covering modules.

Can QR codes expire?

Static QR codes (like the ones this generator creates) do not expire. The encoded data is permanently embedded in the pattern of modules. As long as the physical or digital image is intact and scannable, it will always decode to the same data. Dynamic QR codes from commercial platforms redirect through a short URL that the platform controls — those can be deactivated or redirected by the platform, but the underlying mechanism is just a URL pointing to a redirect server, not the QR standard itself.

Are QR codes secure?

QR codes themselves have no encryption — they simply encode text. Anyone who scans your QR code can read its contents. For sensitive data (passwords, private keys, confidential documents), do not use a QR code — especially one generated through a third-party service. For WiFi QR codes, the network password is embedded in plaintext in the QR data, so anyone who photographs your QR code can join your network. Treat a printed WiFi QR code like a sticky note with your password written on it.

What is a vCard QR code?

A vCard QR code encodes contact information in the vCard 3.0 format, a standard that virtually all smartphones understand. When a user scans the code, their phone offers to add the contact directly to their address book — no app needed. The vCard format includes fields for full name (FN), organization (ORG), phone (TEL), email (EMAIL), and website URL. vCard QR codes are useful on business cards, conference badges, and product packaging so customers can save contact details instantly without typing.