Count CSS selectors on current page

CSSSelectorCounter.js

(function() {
  var styleSheets = document.styleSheets;

  for (var j = 0; j < styleSheets.length; j++) {
    if (styleSheets[j].href) {
      var stylesheet = styleSheets[j];
      var rules = stylesheet.rules;
      var totalSelectors = 0;

      for (var i = 0; i < rules.length; i++) {
        if (rules[i].selectorText) {
          totalSelectors += rules[i].selectorText.split(',').length;
        }
      }

      console.log('---');
      console.log('URL:        ' + stylesheet.href);
      console.log('Rules:      ' + stylesheet.rules.length);
      console.log('Selectors:  ' + totalSelectors);
    }
  }

  return "---";
})()

Instruction.md

1. Add CSSSelectorCounter.js to Chrome Snippets.

2. If CSS is served from external domains (i.e. CDN) open Chrome with disabled same origin policy: open -a Google\ Chrome --args --disable-web-security

3. Run CSS Selector Counter snippet.