font-stretch 属性为字体定义一个正常或经过伸缩变形的字体外观,这个属性并不会通过伸展/缩小而改变字体的几何外形,如font-feature-settingsfont-variant属性,它仅仅意味着当有多种字体可供选择时,会为字体选择最适合的大小。

The two 'e' belong to the same fonts. One is condensed, the other normal and can be selected by 'font-stretch'.

Note: If the font provides several faces, the one fitting the best with the value of the font-stretch property is chosen. E.g. On OS X, in addition to the more common Bold, Regular, Italic, and BoldItalic faces, the "Helvetica Neue" font proposes a second set of faces with condensed, that is shrunk, characters: Condensed. Browsers supporting font-stretch will use the condensed faces for the value ultra-condensed to semi-condensed and the normal faces for the other (normal and all expanded values).

Font-stretch results with a font having 2 faces, one condensed and one normal.

If the font has no condensed or expanded faces, like the default "Times New Roman" on Mac OS, font-stretch will not have any visible effect as the only suitable face will be used in all cases.:
Font-stretch results with a font having 1 single face.

适用元素all elements. It also applies to ::first-letter and ::first-line.
计算值as specified
Animation typea font stretch


/* Keyword values */
font-stretch: ultra-condensed;
font-stretch: extra-condensed;
font-stretch: condensed;
font-stretch: semi-condensed;
font-stretch: normal;
font-stretch: semi-expanded;
font-stretch: expanded;
font-stretch: extra-expanded;
font-stretch: ultra-expanded;

/* Global values */
font-stretch: inherit;
font-stretch: initial;
font-stretch: unset;


semi-condensed, condensed, extra-condensed, ultra-condensed
小于默认字体,其中 ultra-condensed 是缩的最小的字体
semi-expanded, expanded, extra-expanded, ultra-expanded


Font stretch values are interpolated in discrete steps. The interpolation happens as though the ordered values are equally spaced real numbers; the result is rounded to the nearest value, with values exactly halfway between two values rounded towards the later value, that is the most expanded one.

Formal syntax

font-stretch = 
normal |
<percentage> |
ultra-condensed |
extra-condensed |
condensed |
semi-condensed |
semi-expanded |
expanded |
extra-expanded |



<div class="ultra stretch"> This is text with the font extremely expanded</div>
<div class="stretch"> This is text with the font stretched</div>
<div class="normal"> This is text without font stretching</div>
<div class="condensed"> This is text with the font condensed</div>
<div class="ultra condensed"> This is text with the font extremely condensed</div>


.ultra.stretch{font-stretch: ultra-expanded;}
.stretch {font-stretch: expanded;}
.normal {font-stretch: normal;}
.condensed {font-stretch: condensed;}
.ultra.condensed {font-stretch: ultra-condensed;}



Specification Status Comment
CSS Fonts Module Level 3
Recommendation Initial definition

The CSS property font-stretch was initially defined in CSS 2, but dropped in CSS 2.1 due to lack of implementation experience. It has been newly defined in CSS 3.

Browser compatibility

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