CSS speak-as
The CSS speak-as
property is used in speech media to determine how certain text is spoken.
The speak-as
property allows you to specify whether text should be spoken or spelled out, whether or not numbers should be spoken one digit at a time, whether punctuation is spoken literally or rendered naturally, etc.
For example, you could specify whether:
- the word
Ajax
is spoken as "ajax" or each letter is spelled out as "A J A X" - the number
15
is spoken as "fifteen" or "one five" - commas are spoken literally as "comma" or simply rendered as an appropriate pause
Syntax
Possible Values
normal
- Specifies that language-dependent pronunciation rules are used for rendering the element's content. For example, punctuation is not spoken out, but rendered naturally as appropriate pauses.
spell-out
- Spells the text, one letter at a time. This is useful for acronyms and abbreviations. For example, "Ajax" is spelled out as "A J A X".
digits
- Speak the numeral as individual digits. For example,
645
is spoken "Six Four Five". literal-punctuation
- Specifies that punctuation such as semicolons, braces, are spoken literally (rather than rendered naturally as appropriate pauses).
no-punctuation
- Punctuation is not rendered at all. It's neither spoken nor rendered as pauses.
In addition, all CSS properties also accept the following CSS-wide keyword values as the sole component of their property value:
initial
- Represents the value specified as the property's initial value.
inherit
- Represents the computed value of the property on the element's parent.
unset
- This value acts as either
inherit
orinitial
, depending on whether the property is inherited or not. In other words, it sets all properties to their parent value if they are inheritable or to their initial value if not inheritable.
General Information
- Initial Value
normal
- Applies To
- All elements
- Inherited?
- Yes
- Media
- speech
Example Code
Official Specifications
- CSS Speech Module (W3C Candidate Recommendation 20 March 2012)
Vendor Prefixes
For maximum browser compatibility many web developers add browser-specific properties by using extensions such as -webkit-
for Safari, Google Chrome, and Opera (newer versions), -ms-
for Internet Explorer, -moz-
for Firefox, -o-
for older versions of Opera etc. As with any CSS property, if a browser doesn't support a proprietary extension, it will simply ignore it.
This practice is not recommended by the W3C, however in many cases, the only way you can test a property is to include the CSS extension that is compatible with your browser.
The major browser manufacturers generally strive to adhere to the W3C specifications, and when they support a non-prefixed property, they typically remove the prefixed version. Also, W3C advises vendors to remove their prefixes for properties that reach Candidate Recommendation status.
Many developers use Autoprefixer, which is a postprocessor for CSS. Autoprefixer automatically adds vendor prefixes to your CSS so that you don't need to. It also removes old, unnecessary prefixes from your CSS.
You can also use Autoprefixer with preprocessors such as Less and Sass.