Kontraster is a tool to help audit text colour contrast.

npm install kontraster

If you wish to run kontraster as a CLI tool outside of a project, you may want to install kontraster globally:

npm install kontraster -g

const kontraster = require('kontraster');

kontraster(baseImage, overlayImage, {
	isLargeText: false,
	level: 'AA',
	output: './output.png',
	outputType: 'overlay',
});

konstraster <base image> <overlay image> [options]

• --is-large-text: Whether the contents is large text (> 18 points, or > 14 points and bold)
• --level, -l: The WCAG level to test ("AA" or "AAA", defaults to AA)
• --output, -o: The path to write the output image to
• --output-type, -t: The type of output ("composition" or "mask", defaults to composition)
• --help, -h: Show the help message