font - CSS: Cascading Style Sheets 编辑

The font CSS shorthand property sets all the different properties of an element's font. Alternatively, it sets an element's font to a system font.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

As with any shorthand property, any individual value that is not specified is set to its corresponding initial value (possibly overriding values previously set using non-shorthand properties). Though not directly settable by font, the longhands font-size-adjust and font-kerning are also reset to their initial values.

Constituent properties

This property is a shorthand for the following CSS properties:

Syntax

The font property may be specified as either a single keyword, which will select a system font, or as a shorthand for various font-related properties.

If font is specified as a system keyword, it must be one of: caption, icon, menu, message-box, small-caption, status-bar.

If font is specified as a shorthand for several font-related properties, then:

  • it must include values for:
  • it may optionally include values for:
  • font-style, font-variant and font-weight must precede font-size
  • font-variant may only specify the values defined in CSS 2.1, that is normal and small-caps
  • font-stretch may only be a single keyword value.
  • line-height must immediately follow font-size, preceded by "/", like this: "16px/3"
  • font-family must be the last value specified.

Values

<'font-style'>
See the font-style CSS property.
<'font-variant'>
See the font-variant CSS property.
<'font-weight'>
See the font-weight CSS property.
<'font-stretch'>
See the font-stretch CSS property.
<'font-size'>
See the font-size CSS property.
<'line-height'>
See the line-height CSS property.
<'font-family'>
See the font-family CSS property.

System font values

caption
The system font used for captioned controls (e.g., buttons, drop-downs, etc.).
icon
The system font used to label icons.
The system font used in menus (e.g., dropdown menus and menu lists).
message-box
The system font used in dialog boxes.
small-caption
The system font used for labeling small controls.
status-bar
The system font used in window status bars.
Prefixed system font keywords
Browsers often implement several more, prefixed, keywords: Gecko implements -moz-window, -moz-document, -moz-desktop, -moz-info, -moz-dialog, -moz-button, -moz-pull-down-menu, -moz-list, and -moz-field.

Formal definition

Initial valueas each of the properties of the shorthand:
Applies toall elements. It also applies to ::first-letter and ::first-line.
Inheritedyes
Percentagesas each of the properties of the shorthand:
  • font-size: refer to the parent element's font size
  • line-height: refer to the font size of the element itself
Computed valueas each of the properties of the shorthand:
  • font-style: as specified
  • font-variant: as specified
  • font-weight: the keyword or the numerical value as specified, with bolder and lighter transformed to the real value
  • font-stretch: as specified
  • font-size: as specified, but with relative lengths converted into absolute lengths
  • line-height: for percentage and length values, the absolute length, otherwise as specified
  • font-family: as specified
Animation typeas each of the properties of the shorthand:

Formal syntax

[ [ <'font-style'> || <font-variant-css21> || <'font-weight'> || <'font-stretch'> ]? <'font-size'> [ / <'line-height'> ]? <'font-family'> ] | caption | icon | menu | message-box | small-caption | status-bar

where
<font-variant-css21> = [ normal | small-caps ]

Examples

Setting font properties

/* Set the font size to 12px and the line height to 14px.
   Set the font family to sans-serif */
p { font: 12px/14px sans-serif }

/* Set the font size to 80% of the parent element
   or default value (if no parent element present).
   Set the font family to sans-serif */
p { font: 80% sans-serif }

/* Set the font weight to bold,
   the font-style to italic,
   the font size to large,
   and the font family to serif. */
p { font: bold italic large serif }

/* Use the same font as the status bar of the window */
p { font: status-bar }

Live sample

HTML

<p>
    Change the radio buttons below to see the generated shorthand and it's effect.
</p>
<form action="createShortHand()">
    <div class="cf">
        <div class="setPropCont">
            font-style<br/>
            <input type="radio" id="font-style-none" name="font_style" checked="" value="" onchange="setCss()"> <label for="font-style-none">none</label><br/>
            <input type="radio" id="font-style-normal" name="font_style" value="normal" onchange="setCss()"> <label for="font-style-normal">normal</label><br/>
            <input type="radio" id="font-style-italic" name="font_style" value="italic" onchange="setCss()"> <label for="font-style-italic">italic</label><br/>
            <input type="radio" id="font-style-oblique" name="font_style" value="oblique" onchange="setCss()"> <label for="font-style-oblique">oblique</label>
        </div>

        <div class="setPropCont">
            font-variant<br>
            <input type="radio" id="font-variant-none" name="font_variant" checked="" value=" " onchange="setCss()"> <label for="font-variant-none">none</label><br/>
            <input type="radio" id="font-variant-normal" name="font_variant" value="normal" onchange="setCss()"> <label for="font-variant-normal">normal</label><br/>
            <input type="radio" id="font-variant-small-caps" name="font_variant" value="small-caps" onchange="setCss()"> <label for="font-variant-small-caps">small-caps</label>
        </div>

        <div class="setPropCont">
            font-weight<br/>
            <input type="radio" id="font-weight-none" name="font_weight" value="" onchange="setCss()"> <label for="font-weight-none">none</label><br/>
            <input type="radio" id="font-weight-normal" checked="" name="font_weight" value="400" onchange="setCss()"> <label for="font-weight-normal">normal</label><br/>
            <input type="radio" id="font-weight-bold" name="font_weight" value="700" onchange="setCss()"> <label for="font-weight-bold">bold</label>
        </div>

        <div class="setPropCont">
            font-size<br/>
            <input type="radio" id="font-size-12px" name="font_size" value="12px" onchange="setCss()"> <label for="font-size-12px">12px</label><br/>
            <input type="radio" id="font-size-16px" name="font_size" value="16px" checked="" onchange="setCss()"> <label for="font-size-16px">16px</label><br/>
            <input type="radio" id="font-size-24px" name="font_size" value="24px" onchange="setCss()"> <label for="font-size-24px">24px</label>
        </div>

        <div class="setPropCont">
            line-height<br/>
            <input type="radio" id="line-height-none" name="line_height" checked="" value="" onchange="setCss()"> <label for="line-height-none">none</label><br/>
            <input type="radio" id="line-height-1.2" name="line_height" value="/1.2" onchange="setCss()"> <label for="line-height-1.2">1.2</label><br/>
            <input type="radio" id="line-height-3" name="line_height" value="/3" onchange="setCss()"> <label for="line-height-3">3</label>
        </div><br/>

        <div class="setPropCont fontfamily">
            font-family<br/>
            <input type="radio" id="font-family-courier" name="font_family" checked="" value="courier" onchange="setCss(5,'courier')"> <label for="font-family-courier">courier</label><br/>            <input type="radio" id="font-family-serif" name="font_family" value="serif" onchange="setCss()"> <label for="font-family-serif">serif</label><br />
            <input type="radio" id="font-family-sans-serif" name="font_family" value="sans-serif" onchange="setCss()"> <label for="font-family-sans-serif">sans-serif</label><br />            <input type="radio" id="font-family-arial" name="font_family" value="arial" onchange="setCss()"> <label for="font-family-arial">Arial</label><br />
            <input type="radio" id="font-family-monospace" name="font_family" value="monospace" onchange="setCss()"> <label for="font-family-monospace">monospace</label><br />            <input type="radio" id="font-family-cursive" name="font_family" value="cursive" onchange="setCss()"> <label for="font-family-cursive">cursive</label><br />
            <input type="radio" id="font-family-fantasy" name="font_family" value="fantasy" onchange="setCss()"> <label for="font-family-fantasy">fantasy</label><br />            <input type="radio" id="font-family-system-ui" name="font_family" value="system-ui" onchange="setCss()"> <label for="font-family-system-ui">system-ui</label><br />
        </div>
    </div>

    <div class="cf propInputs">
        <div class="propInputCont tar">
            font :
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss" id="input_font_style"><br/>
            font-style <br/>
            optional

        </div>
        <div class="propInputCont">
            <input type="text" class="curCss" id="input_font_variant"> <br/>
            font-variant <br/>
            optional
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss" id="input_font_weight"> <br/>
            font-weight <br/>
            optional
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss mandatory" id="input_font_size"> <br/>
            font-size <br/>
            mandatory
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss" id="input_line_height"> <br/>
            line-height <br/>
            optional
        </div>
        <div class="propInputCont">
            <input type="text" class="curCss mandatory" id="input_font_family"> <br/>
            font-family <br/>
            mandatory
        </div>
    </div>
</form>

<div class="fontShortHand">
    This is some sample text.
</div>
<br/><br/><br/><br/><br/><br/>

CSS

body, input {
  font: 14px arial;
  overflow: hidden;
}

.propInputCont {
  float: left;
  text-align: center;
  margin-right: 5px;
  width: 80px;
}

.setPropCont {
  float: left;
  margin-right: 5px;
  width: 120px;
}

.propInputs, .setPropCont {
  margin-bottom: 1em;
}

.curCss {
  border: none;
  border-bottom: 1px solid black;
  text-align: center;
  width: 80px;
}

.mandatory {
  border-bottom-color: red;
}

.cf:before,
.cf:after {
  content: " ";
  display: table;
}

.cf:after {
  clear: both;
}

.tar {
  width: 40px;
  text-align: right;
}
.fontfamily {
  display: inline-block;
}

JavaScript

var textAreas = document.getElementsByClassName("curCss"),
    shortText = "",
    getCheckedValue,
    setCss,
    getProperties,
    injectCss;

getProperties = function () {
  shortText =
      getCheckedValue("font_style") + " " +
      getCheckedValue("font_variant") + " " +
      getCheckedValue("font_weight") + " " +
      getCheckedValue("font_size") +
      getCheckedValue("line_height") + " " +
      getCheckedValue("font_family");

  return shortText;
}

getCheckedValue = function(radio_name) {
  oRadio = document.forms[0].elements[radio_name];
  for (var i = 0; i < oRadio.length; i++) {
    if(oRadio[i].checked) {
      var propInput = "input_" + radio_name,
          curElemName = "input_" + radio_name,
          curElem = document.getElementById(curElemName);
      curElem.value = oRadio[i].value;

      return oRadio[i].value;
    }
  }
}

setCss = function () {
  getProperties();
  injectCss(shortText);
}

injectCss = function(cssFragment) {
  old = document.body.getElementsByTagName("style");
  if (old.length > 1) {
    old[1].parentElement.removeChild(old[1]);
  }
  css = document.createElement("style");
  css.innerHTML = ".fontShortHand{font: " + cssFragment + "}";
  document.body.appendChild(css);
}

setCss();

Specifications

SpecificationStatusComment
CSS Fonts Module Level 3
The definition of 'font' in that specification.
RecommendationAdded support for font-stretch values.
CSS Level 2 (Revision 1)
The definition of 'font-weight' in that specification.
RecommendationAdded support for keywords.
CSS Level 1
The definition of 'font' in that specification.
RecommendationInitial definition.

Browser compatibility

BCD tables only load in the browser

See also

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