CalcaTools

QR Code Generator | Create QR Codes for URLs, Text & Wi-Fi

Generate QR codes for URLs, text and more instantly in your browser — with Reed-Solomon error correction, color choices and high-resolution download. Private (nothing uploaded) and works forever.

Last updated: June 2026 · Free · No sign-up required

Enter a URL and click Generate.

Quick reference

Content typeFormat
Websitehttps://example.com
Wi-FiWIFI:T:WPA;S:network;P:password;;
Phonetel:+15551234567
Emailmailto:hi@example.com
SMSsms:+15551234567

info QR Code Generator

Free image tools calculator — enter your numbers and get an instant, accurate result.

info Private by design

Everything runs locally in your browser. No uploads, no accounts, no tracking.

info Works everywhere

Fully responsive and mobile-friendly — calculate on any device, any time.

info Educational

Includes the formula and step-by-step explanation so you understand the math, not just the answer.

Interpretation guide

Print sizeMin scan distance rule
2×2 cmBusiness cards (close scan)
5×5 cmFlyers, menus
10×10 cm+Posters — size ≈ distance ÷ 10

lightbulb Worked example

Let's say you are using the QR Code Generator. A free tool to generate custom QR codes for URLs, text, Wi-Fi networks, and more. Customize colors and size, then download as a high-quality PNG. All generation runs in your browser. Enter the values that match your situation into the input fields and press calculate — using realistic numbers makes the result directly useful for you.

Result: The calculator instantly applies the formula QR = Reed-Solomon-encoded modules; capacity up to ~4,296 alphanumeric chars (v40) and returns the result with appropriate precision.

What this means: Read the result in the context of what you are measuring. The step-by-step breakdown lets you confirm the math and understand which input most affects the outcome.

Formula & methodology

Formula: QR = Reed-Solomon-encoded modules; capacity up to ~4,296 alphanumeric chars (v40)

The QR Code Generator is built on a well-established calculation method. It uses the formula QR = Reed-Solomon-encoded modules; capacity up to ~4,296 alphanumeric chars (v40) to turn your inputs into a reliable result. A free tool to generate custom QR codes for URLs, text, Wi-Fi networks, and more. Customize colors and size, then download as a high-quality PNG. All generation runs in your browser. The steps are shown on the page so you can follow the reasoning from input to output.

  1. Enter the URL or text (use the formats above for Wi-Fi, phone, email actions).
  2. The generator encodes it with error correction into the QR module grid, locally in your browser.
  3. Set the pixel size and download the PNG.

Worked example: a typical https URL encodes into a version-3–5 code that scans reliably at 2×2 cm print size; adding UTM parameters lengthens the URL and densifies the grid — shorten links for small prints.

Frequently asked questions

Do these QR codes expire?
No — QR codes are static images of the data you encode, so they work forever until the destination changes. The generator creates the code locally in your browser with Reed-Solomon error correction and no expiry or scan tracking. Only dynamic QR services that redirect through their own server can expire or track scans, which this tool does not use.
How do I make a Wi-Fi QR code?
Enter the required values into the input fields and press the calculate button. The tool applies the formula QR = Reed-Solomon-encoded modules; capacity up to ~4,296 alphanumeric chars (v40) and returns the result with a short explanation of each step, so you can check the working yourself.
How small can I print a QR code?
The QR Code Generator is free, private, and accurate: it runs entirely in your browser (no uploads, no accounts), applies the standard calculation, and explains each step so you can verify the result. A free tool to generate custom QR codes for URLs, text, Wi-Fi networks, and more. Customize colors and size, then download as a high-quality PNG. All generation runs in your browser. There is no limit on usage, and it works on any device.
Why won’t my QR code scan?
Common causes: insufficient contrast (light colors on light backgrounds), damage or blur, too-small printing, a white border missing around the code, or the camera holding the code too far or too close. QR codes need a quiet zone of at least 4 modules around the pattern and a minimum printed size of about 2 cm. The generator includes the quiet zone by default and warns on low-contrast color choices.
Can I track QR code scans?
Not with this tool — it generates static QR codes with no tracking built in. Static codes simply encode the URL or text; they cannot report who scanned them. If you need scan analytics, use a dynamic QR service that wraps the destination in a redirect URL, or add your own analytics parameter to the target link. The generator focuses on privacy and offline functionality.
What does the QR Code Generator do?
A free tool to generate custom QR codes for URLs, text, Wi-Fi networks, and more. Customize colors and size, then download as a high-quality PNG. All generation runs in your browser. The calculator takes your inputs, applies the standard calculation, and returns a clear result so you can make an informed decision without doing the math by hand.
What formula does the QR Code Generator use?
It encodes the data into QR modules using Reed-Solomon error correction, with capacity up to about 4,296 alphanumeric characters at version 40. The encoding adds error-correction bytes so the code stays scannable even when up to 30% is damaged, then arranges the modules with the finder patterns. The generator produces this standard-compliant QR locally in your browser.
Is the QR Code Generator free and private?
Yes — the QR Code Generator. There is no sign-up, no paywall, no trial, and no limit on how many calculations you can run. CalcaTools covers its costs with non-intrusive display advertising, so the calculator itself never asks for payment or restricts any feature.
How accurate is the QR Code Generator?
The QR Code Generator applies the standard formula: QR = Reed-Solomon-encoded modules; capacity up to ~4,296 alphanumeric chars (v40). It is tested against published worked examples before launch and uses native double-precision arithmetic, so results are accurate to typical precision for the values you enter — with no intermediate rounding that could distort the answer.

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