Flesch-Kincaid Calculator for WordPress

<?php
/**
 * Custom Open Graph & Twitter Cards without plugins in WordPress
 */
function omni_custom_social_meta_tags() {
    global $post;
    if (is_singular()) {
        $title = get_the_title();
        $description = wp_strip_all_tags(get_the_excerpt() ? get_the_excerpt() : wp_trim_words($post->post_content, 25));
        $url = get_permalink();
        $thumb_id = get_post_thumbnail_id();
        $image = $thumb_id ? wp_get_attachment_image_url($thumb_id, 'large') : get_site_icon_url(1200);
        
        echo '<meta property="og:type" content="article" />' . "
";
        echo '<meta property="og:title" content="' . esc_attr($title) . '" />' . "
";
        echo '<meta property="og:description" content="' . esc_attr($description) . '" />' . "
";
        echo '<meta property="og:url" content="' . esc_url($url) . '" />' . "
";
        echo '<meta property="og:site_name" content="' . esc_attr(get_bloginfo('name')) . '" />' . "
";
        if ($image) {
            echo '<meta property="og:image" content="' . esc_url($image) . '" />' . "
";
        }
        echo '<meta name="twitter:card" content="summary_large_image" />' . "
";
        echo '<meta name="twitter:title" content="' . esc_attr($title) . '" />' . "
";
        echo '<meta name="twitter:description" content="' . esc_attr($description) . '" />' . "
";
        if ($image) {
            echo '<meta name="twitter:image" content="' . esc_url($image) . '" />' . "
";
        }
    }
}
add_action('wp_head', 'omni_custom_social_meta_tags', 5);