Contrast Ratio Calculator
Accessibility library that calculates contrast ratios of colors as well as rates the contrast ratio against WCAG standards.
Getting started
- PHP 7.1.x is required
- Install the Contrast Ratio Calculator using Composer (recommended) or manually
Composer Installation
- Get Composer
- Install with
composer require harmstyler/contrast-ratio-calculator - Add the following to your application's main PHP file:
require 'vendor/autoload.php';
Usage
<?php
use HarmsTyler\ContrastRatioCalculator\Color;
use HarmsTyler\ContrastRatioCalculator\ContrastRatio;
use HarmsTyler\ContrastRatioCalculator\WCAGContrastRating;
$primaryColor = new Color();
$primaryColor->setHex('#ffffff');
$secondaryColor = new Color();
$secondaryColor->setHex('#000000');
$contrastRatio = new ContrastRatio($primaryColor, $secondaryColor);
echo $contrastRatio->getRatio(); // floating decimal point of calculated ratio
$rating = new WCAGContrastRating();
echo $rating->rateContrastRatio($contrastRatio); // the WCAGContrast grade, either 'fail', 'aa-large', 'aa', or 'aaa'Run the tests
./vendor/bin/phpunit tests/
