QRcode.show
A free QR code generation service reachable entirely through curl, turning any text or file piped to it into a QR code as an image, SVG, or plain text, with configurable size, color, and error-correction level.
QRcode.show generates QR codes through a simple HTTP API designed to be used directly from curl, either by appending the input to the URL, posting it as data, or piping a file or standard input into the request. Output format is chosen through the standard accept header, supporting PNG, JPEG, SVG, plain text, or raw bytes, and further headers control the code's width, height, error-correction level, version, quiet zone, and dark and light colors.
Example shell functions are provided for generating a QR code from the command line or from a script, using either GET or POST requests. The service states that it does not collect or retain submitted data.
It is written in Rust and HTML and distributed under the AGPL-3.0 license.