Webmasters Stack Exchange is a question and answer site for pro webmasters. Join them; it only takes a minute:

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Making something bold makes it more important for search engine ranking and even improves readability for humans.

To get the search engine ranking benefit, do we need to use <b> or <strong> tag or are CCS rules to do this recognized?

In other words, do search engine crawlers actually read and apply CSS when analyzing content?

share|improve this question
up vote 4 down vote accepted

The generally accepted way to emphasise text is to use the <strong> tag. You can then style that using CSS.

Looking through our logs I can see some evidence that some spiders fetch CSS files. Specifically,

  • Googlebot-Image/1.0
  • DoCoMo/2.0 (compatible; Googlebot-Mobile/2.1)
  • Googlebot (http://www.google.com/bot.html)

Anecdotally there's evidence that some search engines use this to detect if text is being hidden (and therefore someone is trying to fool a search engine with bogus keywords).

I think your safest bet is to use <strong> and don't rely purely on CSS to emphasise important words or phrases.

share|improve this answer
+1 for theory and taking the conservative approach – John Conde May 13 '11 at 2:01

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.