WP - Truncate Field Content

wp-truncate-field.php

function truncate_field($title) {
  global $post;
  $text = get_field($title);
  if ( '' != $text ) {
    $text = strip_shortcodes( $text );
    $text = apply_filters('the_content', $text);
    $text = str_replace(']]>', ']]>>', $text);
    $text_length = strlen($text); // Get text length (characters)
    $excerpt_length = 100;  // 50 desired characters
    $excerpt_more = '...';

    // Shorten the text
    $text = substr($text, 0, $excerpt_length);

    // If the text is more than 50 characters, append $excerpt_more
    if ($text_length > $excerpt_length) {
      $text .= $excerpt_more;
    }

  }
  return apply_filters('the_excerpt', $text);
}

<!-- add below to template -->
<?php echo truncate_field('field_name'); ?>