Initial width

width

Specify the element's initial width.

Property values

This value has two different interpretations depending upon the current value of the element's box-sizing property.

box-sizing: content-box The width is the size of the element's content area only
box-sizing: border-box The width is the sum of the element's content area plus the size of its left-padding and right-padding plus the thickness of its left-border and right-border

Units

Use any of these font-relative typographic units to set the element's width:

em em The font-size of the current font
rem relative em The font-size of the <html> element
ch "0" The advance measure (the width) of the current font's "0" glyph
ic ideograph count The advance measure (the width) of the current font's "水" ideograph

Or use any of these fixed size units which are independent of the current font:

% percent A percentage of the parent element's width
in inch A size equal 96px
px pixels A size equal to 1/96 inch
pt point A size equal 1in/72 = 1.33px
pc pica A size equal 1in/6 = 12pt = 16px
cm centimeter A size equal to 96px/2.54 = 37.8px
mm millimeter A size equal to 96px/25.4 = 3.8px
Q quarter millimeter A size equal to 96px/1016 = 0.94px

Or use these viewport-percentage units which account for different display device capabilities:

vh viewport height 1% of the viewport's height
vw viewport width 1% of the viewport's width
vi viewport inline axis 1% of the viewport's inline axis
vb viewport block axis 1% of the viewport's block axis
vmin viewport minimum Either vh or vw, whichever is smaller
vmax viewport maximum Either vh or vw, whichever is larger

Examples

width: 200px;
width

style > sizing > widthInitial width

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