I see a few examples of use after doing a search. I don't see code examples though.

I did find
javascript:alert('text/html = '+(b=document.body).innerText.length/b.innerHTML.length);void(0);

in a comment at Search Engine Optimization: Textarea and HTML comments - CodingForums.com

Unfortunately I'm not proficient in Javascript :/

I don't want to cut the possibility of doing Javascript - but I need a better tutorial in order to implement it ...

Anyone with a better solution?

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I am currently building a tool to analyse this as it is an important factor for SEO.

jassmee, I am not looking for the actual size in pixels - I need the ratio of html characters to content characters.

KirkMcD is the one who got the closest ... thought there might be something ready for use out there though!

You can try something below, if your real intention is to find out keyword density.

$content = strip_tags($html_content);
$len = strlen($content);

foreach($keyword_array as $keyword)
{
$found = substr_count($content, $keyword);
$keyword_density[$keyword] = ($found / $content);
}

Well, I really don't think keyword density is really important now, since Google just changed its SEO algo again.

I was searching for Content/HTML ratio - followed KirkMcD's suggestion and it worked.

Yeps, keyword density is next - traderookie's code gave errors. Will see how to go about it.

I am sure both factors still affect Google's algorithm.