QR and barcode questions

How this generator handles your data, which formats it supports, and why.

The short version

Codes are generated in your browser. Nothing you type is sent anywhere, there is no shortener or redirect, and no scan is ever counted.

Frequently asked questions

Is anything I type sent to a server?
No. The encoders run in the page, the images are drawn on a canvas on your device, and downloads are produced locally. Open your browser’s network panel while you use the tool and you will see no request carrying your data.
Which QR types are supported?
Link, plain text, email, telephone, SMS, Wi-Fi and contact card (vCard). Each one builds the standard payload format that phone cameras recognise.
Is Code 128 supported?
Yes. Code 128 is generated with the encoder from JsBarcode, which is MIT-licensed and has no dependencies of its own. It covers ASCII characters and automatically uses the compact numeric mode for digit strings, so a long number produces a shorter barcode.
Why are other barcode formats missing?
Scope. Code 128 covers the general-purpose cases most people need — asset tags, shipping references, inventory. EAN and UPC are tied to registered product numbering and are easy to produce incorrectly, so they are deliberately left out rather than shipped half-right.
Why does my accented text work in a QR code but not a barcode?
QR codes here are encoded as UTF-8 bytes, so any text works. Code 128 is an ASCII-only symbology — there is no way to represent an accented character in it, so the tool tells you which characters to remove rather than silently dropping them.
PNG or SVG?
SVG for print, because it is vector and scales without blurring. PNG for screens and documents. Never scale an exported PNG up afterwards; re-export it at the size you need.
What does the contrast figure next to the preview mean?
The ratio between the lightness of your two colours, from 1:1 (identical) to 21:1 (black on white). Aim for 7:1 or better. The tool warns below about 4:1 and warns strongly below 2:1, because scanners convert the image to black and white before reading it.
Can I make a transparent code?
Yes, for PNG and SVG. Be careful: whatever ends up behind the code still has to be light enough to give good contrast, and the preview’s checkerboard is there to remind you that the background is not white.
Can I decode or scan a code with this tool?
Not currently. It generates codes only. Your phone’s camera app already decodes them well.
Does the Wi-Fi code work on both Android and iPhone?
The WIFI: payload format is recognised by the built-in camera apps on current Android and iOS. Very old devices may not support it, and some corporate network configurations cannot be expressed in the format at all.

What this tool will not do