About Zizmix

Zizmix is an independent project that builds free QR code tools and writes practical guides about using them well.

Why this site exists

Generating an image is only one step in publishing a useful QR code. The printed result also depends on size, contrast, margin, density and a working destination. We built tools that check for those problems, and guides that explain the reasoning so you can make your own decisions.

What the tools do

QR Code Generator: links, text, Wi-Fi, contact cards, email, phone and SMS, with PNG and SVG download.
QR Contrast Checker: the WCAG contrast ratio between code and background, with a live preview.
QR Size Calculator: minimum print width from the scanning distance and your data.
QR Capacity Checker: the version and grid your text needs at each error-correction level.

How we check our work

Encoder: an open-source library (qrcode-generator by Kazuhiko Arase, MIT licence) hosted on this site, extended with UTF-8 encoding and automatic selection of numeric, alphanumeric or byte mode.
Public checks: the verification page generates synthetic URL, text, Wi-Fi, contact, email, phone and SMS payloads, then decodes them with jsQR. You can rerun it locally in your browser and inspect each result. This is a software check, not a camera or printer certification.
Capacity: the tools encode your actual input at each correction level to find the grid it needs. The public checks include version-one capacity boundaries and the maximum byte capacity at level L. Reference limits are linked in the capacity guide.
Contrast: the WCAG relative-luminance formula. The public checks include black on white (21:1) and identical colours (1:1). Contrast bands are planning hints, not a QR scan standard.

Editorial responsibility and policy

Zizmix is responsible for these tools and guides. The byline identifies the project, not an independent testing laboratory. Technical examples are reproducible calculations; a hypothetical workflow is labelled as such. Questions and corrections go to zizmix@gmail.com.

Accuracy first. Technical claims are checked against the QR code standard or reproduced with our own tools. Where a number is a rule of thumb, such as the 10:1 distance rule or our contrast bands, we say so.
Helpful, not promotional. Guides explain how to decide, and where a free approach exists we say so, even when it means you do not need a paid service.
No made-up experience. We do not invent case studies or testimonials. Where we give a measurement, you can repeat it in the tools.
No professional advice. Content on tax, privacy rules, allergen labelling or similar topics is general information only, and we tell you to check local requirements.
Corrections. If you find an error, email zizmix@gmail.com. We review reports promptly and note significant changes with an updated date.
Updates. Each guide shows when it was last reviewed.

Advertising and independence

Zizmix has applied to Google AdSense. This version does not load advertising or analytics scripts. If advertising is enabled later, it will not influence the guides or tools; privacy disclosures and consent controls must reflect that change. Details of how ads and cookies work are in our privacy policy.

Contact

Questions, corrections or tool requests: zizmix@gmail.com or the contact page. We usually reply within two working days.

QR Code is a registered trademark of DENSO WAVE INCORPORATED. Zizmix is not affiliated with Denso Wave.