Sentinel: Your Web-Performance Watchman

A reconsideration—in defence of <b> and <i> (or: people fear what they don’t understand)

Written by on CSS Wizardry.

Table of Contents
  1. What the facts state
  2. Twitter
    1. Some replies
    2. What about strong and em?
      1. The screenreader fallacy
    3. Where to use <b> and <i> then?
      1. HTML5 has it sussed
        1. The <b> element in HTML5
        2. The <i> element in HTML5
    4. A go-between in the meantime?
    5. The resolve?

The other day, I got to thinking about the HTML elements <b> and <i>, and wondered if they were still viably usable in production code. I’ve personally never used them before but I was aware that they existed and were still very much valid XHTML markup (even in the Strict DOCTYPE!). Wondering whether I’d avoided two elements for three years unnecessarily, I did some digging.

What the facts state

<b> and <i> are still valid, and as XHTML is just an XML serialisation of HTML, pretty much all the elements apparent in the HTML spec are true of the XHTML spec too–it is, pretty much, just the way in which these elements are written that makes them different in XHTML.


With the help of @smashingmag I turned to Twitter and my knowledgeable followers and asked the question:

Using <i> and <b> in (valid) XHTML (strict)… your thoughts on this would be much appreciated. #upcomingBlogPost Cheers all! @csswizardry

Most of the answers I got said petty much the same thing: use strong and emb and i are deprecated. While this is largely true, there are some myths that need dispelling.

  • strong and em are not the same as bold and italics. strong is strong emphasis and em is emphasis. It is purely through convention that these two elements happen to adopt either bold or italicised appearances.
  • b and i are not deprecated in any way in HTML or XHTML. They are still in existence, still valid and still (in the right places) usable.

Some replies

A few choice replies I received which are, on the whole, representative of everyone’s thoughts:

strong and em make more sense, especially when taking screen readers into account. @CreativeNotice

Or so you’d think, see below…

I prefer <strong> <em> because of semantics. You want to put emphasis, not just make text italic. @WeHelpDesign

True, if you do just want emphasis that is…

Using <i> and <b> is just fine if it’s for visual bling without real semantic background. @levito

Ah, this is more like it!

<b> and <i> tags describe presentation, not structural semantics. Rather style <em> and <strong> tags. @hornergraphic

A view that is seemingly shared by almost everyone else who responded.

What about strong and em?

The vast majority of people who replied were in favour of strong and em over b and i. Presuming all respondents were assuming the question was ‘What are your thoughts on using b and i to represent strong emphasis and emphasis, and thus replace strong and em?’ then they’d have all been spot on correct. However, b and i and strong and em are totally separate things. b and i assume no semantic value, meaning literally bold and italic respectively. strong and em however have nothing to do with bold or italics. As previously mentioned, it is through convention only that the default styling for each is so.

strong and em are ‘spoken word’ type elements, where they represent a change in tone only. This means that their styling is in no way linked to their naming, it is just that us, as people, are familiar with italicised prose sounding more stressed–or emphasised–than surrounding text. This is where the importance of aforementioned semantics and screenreaders come in. Or is it…?

The screenreader fallacy

Screenreaders don’t use strong and em!

The common belief is that strong and em’s semantic meaning is used by screenreaders to alter tonality when reading content aloud, thus letting the user know that the copy is in fact meant to be understood in a different manner to any neighbouring text. This was something I too believed until the wonderfully knowledgeable @pekingspring pointed me toward this article by @stevefaulkner–it turns out screenreaders don’t use strong and em to alter tonality!

This means that screenreaders see no semantic value in the strong and em element. However, they should be used unconditionally where a change in tone is implied, whether a screenreader will understand this or not.

Where to use <b> and <i> then?

One of my first thoughts was where to use these elements if indeed they are still usable. My initial idea was the use of i for markup up things that have to be italicised but the italics aren’t indicative of any tone. To quote the Penguin Guide to Punctuation:

Another use of italics … is to cite titles of complete works…

Initially I thought this was the ideal use for the i element–something that had to be in italics, yet implied no tone of voice. It was such a good fit! However, @pekingspring came to my aid again and reminded me that the cite element is for this exact purpose. That was that idea gone.

Another possible usage for the i element was gleaned from the Typography Manual iPhone app, which states:

Italics should be used for single letters in a sentence referred to as letters. [for] example ‘The letter j appears too large.’

An idea I had for using b was somewhat linked to the cite element anyway. A common mistake is to markup the ‘author’ of a quote in cite tags. This is of course incorrect, but what do you use? It’s not really a paragraph, so what is it? I did consider the b element for this, but I feel that such a piece of information does need a more semantic element to represent it.

Friend and colleague @simonwiffen has a very nicely written example usage for each, which I personally think are spot on. The following chunk of text is lifted directly from an internal document written by @simonwiffen:

1.4.3 Strong, emphasis, bold and italic

<strong> (strong emphasis) and <em> (emphasis) should be used as opposed to <b> (bold) and <i> (italic) unless the bold or italic is required without any semantic context (for example in a product name).


Remember you must check this box

<p>Remember <strong>you must</strong> check this box.</p>

You should really try to validate your pages

<p>You should <em>really</em> try to validate your pages</p>

Read more about Splashdown!™ below

<p>Read more about <b>Splash<i>down</i>!™</b> below</p>

Succinct and, in my opinion, pretty hard to argue with.

HTML5 has it sussed

I won’t be using HTML5 for a long while yet, but that’s another story altogether…

Ideally I’d like to retrofit the HTML5 specification’s definitions of each for use right now in XHTML, however I’m not sure I’d be comfortable going ahead with doing such a thing, coding to one spec whilst picking my favourite bits of another.

The <b> element in HTML5

The `b` element represents a span of text to be stylistically offset from the normal prose without conveying any extra importance, such as key words in a document abstract, product names in a review, or other spans of text whose typical typographic presentation is boldened.

The <i> element in HTML5

The i element represents a span of text in an alternate voice or mood, or otherwise offset from the normal prose, such as a taxonomic designation, a technical term, an idiomatic phrase from another language, a thought, a ship name, or some other prose whose typical typographic presentation is italicized.


A go-between in the meantime?

There will always be the argument that instead of using b and i you could or should use something like or so as to avoid using insemantic elements, however a class name like that is more insemantic than an in-spec HTML element. Not to mention the fact that a span with a class applied is far more cumbersome than a ‘pre-made’ piece of HTML.

The resolve?

So which is worse?

  • Using i to mark up emphasised text
  • Using em to mark up italicised and non-emphasised text
  • Using i to mark up purely italicised text
  • Using <span class="italics"> to mark up italicised text

Special thanks to the following for help with this article: @smashingmag, @pekingspring, @stevefaulkner, @simonwiffen and all my Twitter followers.

I think that the fact that b and i are still in the spec, are valid (even in strict) and are being carried over to HTML5 (albeit slightly redefined) indicates that there is still a very real place for them in web development right now. The frequency with which they’ll be used is slim at best, but they should not be ruled out, and at the very least not misunderstood. I’m not going to make the leap myself just yet, but they are there, they are usable, and one day I might just use them.

What are you going to do?

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Hi there, I’m Harry Roberts. I am an award-winning Consultant Web Performance Engineer, designer, developer, writer, and speaker from the UK. I write, Tweet, speak, and share code about measuring and improving site-speed. You should hire me.

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