qrtool is a command-line utility for encoding or decoding QR code.

cargo install qrtool

The release page contains pre-built binaries for Linux, macOS and Windows.

Please see BUILD.adoc.

Encode a string in a QR code:

qrtool encode "QR code" > output.png

Generate this image:

Decode a QR code from this image:

qrtool decode output.png

Output:

QR code

Use -t option to change the format of the generated image. The format is png (default), svg or terminal (to the terminal as UTF-8 string).

qrtool encode -o output.svg -t svg "QR code"

Generate this image:

Use --variant option to change the variant of the generated QR code. The variant is normal (default) or micro (Micro QR code).

qrtool encode -v 3 --variant micro "QR code" > output.png

Generate this image:

Use --foreground and --background options to change the foreground and background colors of the generated image. These options takes a CSS color string such as brown, #a52a2a or rgb(165 42 42). The default foreground color is black and the background color is white of CSS's named colors.

qrtool encode --foreground brown --background lightslategray "QR code" > output.png

Generate this image:

qrtool decode supports decoding a QR code from the following image formats:

• BMP
• DDS
• Farbfeld
• GIF
• Radiance RGBE
• ICO¹
• JPEG
• OpenEXR
• PNG
• PNM
• QOI
• SVG²
• TGA
• TIFF
• WebP

To support decoding from SVG image, the decode-from-svg feature must be enabled at compile time. Note that the SVG image is rasterized before scanning.

Use -t option to specify the image format. If this option is not specified, the image format is determined based on the extension or the magic number.

Input this WebP image:

Decode a QR code from the WebP image:

qrtool decode input.webp
# or
qrtool decode -t webp input.webp

Output:

QR code

--generate-completion option generates shell completions to stdout.

The following shells are supported:

• bash
• elvish
• fish
• nushell
• powershell
• zsh

Example:

qrtool --generate-completion bash > qrtool.bash

Both qrtool encode and qrtool decode can read from stdin and output to stdout.

The image output by qrtool encode is not optimized. For example, a PNG image is always output as the 32-bit RGBA format. If you want to reduce the image size or optimize the image, use an optimizer such as oxipng or svgcleaner.

Optimize the output PNG image:

qrtool encode "QR code" | oxipng - > output.png

Optimize the output SVG image:

qrtool encode -t svg "QR code" | svgcleaner -c - > output.svg

If you want to save the encoded image in an image format other than PNG or SVG, or decode an image in an unsupported image format, convert it using a converter such as ImageMagick.

Read Cargo.toml from stdin and save the encoded result as a JPEG XL image:

cat Cargo.toml | qrtool encode | magick png:- output.jxl

Decode this image and print the result using bat:

magick output.jxl png:- | qrtool decode | bat -l toml

Please see the following:

• qrtool(1)
• qrtool-encode(1)
• qrtool-decode(1)
• qrtool-help(1)

Please see CHANGELOG.adoc.

Please see CONTRIBUTING.adoc.

This program is inspired by qrencode and zbarimg.

Copyright © 2022–2023 Shun Sakai (see AUTHORS.adoc)

1. This program is distributed under the terms of either the Apache License 2.0 or the MIT License.
2. Some files are distributed under the terms of the Creative Commons Attribution 4.0 International Public License.

This project is compliant with version 3.0 of the REUSE Specification. See copyright notices of individual files for more details on copyright and licensing information.