The <b>, <i> & <u> elements
The <b>, <i> and <u> tags are not deprecated, but in modern HTML each has a specific meaning. <b> draws attention to keywords without making them more important, <i> marks text in an alternate voice such as a foreign phrase or technical term, and <u> marks a non-textual annotation like a spelling error.
Last updated: October 3, 2026
Quick facts
| Category | Flow content, phrasing content, palpable content |
| Content model | Phrasing content |
| Tag omission | Neither the start nor the end tag can be omitted |
| Permitted parents | Any element that accepts phrasing content |
| DOM interface | HTMLElement (all three) |
Syntax
Live example
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Attributes
| Attribute | Description |
|---|---|
| — | All three accept only the global attributes. Add lang to an <i> that holds a foreign phrase so screen readers pronounce it correctly. |
Common examples
Keywords in a summary
<b> draws attention to words without making them more important.
Foreign words and technical terms
<i> is for text in a different voice, such as foreign phrases, taxonomy names or thoughts. Add lang for foreign words.
Marking a spelling mistake
<u> is for an unarticulated annotation, such as a misspelled word in a teaching example.
The lead sentence of an article
A bold opening sentence is a classic use of <b>.
<b> & <i> vs <strong> & <em>
They look the same by default, but say different things. <strong> and <em> add meaning: importance and spoken stress. <b> and <i> only set text apart from its surroundings without saying it’s more important.
Ask yourself: would the meaning change if the formatting disappeared? If yes (a warning, a stressed word), use strong or em. If it’s a convention — a product name, a foreign word, a ship’s name — use b or i.
| <b> / <i> | <strong> / <em> | |
|---|---|---|
| Adds importance or stress | No | Yes |
| Default look | Bold / italic | Bold / italic |
| Example | Product names, foreign words | Warnings, stressed words |
Common mistakes to avoid
- Using u for emphasis. Underlined text looks like a link and confuses visitors.
- Using b for headings. Use real heading tags so the page has a structure.
- Using i for icons.
<i class="icon">is a habit from icon libraries; a<span aria-hidden="true">is more correct. - Using b or i only for design. If there’s no convention behind it, use CSS classes.
Accessibility & SEO tips
- Add
langto foreign words in<i>so screen readers pronounce them correctly. - Avoid underlining anything that isn’t a link — it’s one of the most common usability complaints.
- Bold and italic don’t boost SEO; use them to help readers scan.
- Add a CSS class to b or i when you style them, such as
<b class="product">, so you can change the look later without touching every page.
Browser support
Supported in every browser, including Chrome, Edge, Firefox, Safari and their mobile versions — it has been part of HTML since the very first versions.