2.1.45 [CSS-Level2-2009] Section 9.4.2, Inline formatting context


The specification states:

 In an inline formatting context, boxes are laid out horizontally, one after the other, beginning at the top of a containing block. Horizontal margins, borders, and padding are respected between these boxes. The boxes may be aligned vertically in different ways: their bottoms or tops may be aligned, or the baselines of text within them may be aligned. The rectangular area that contains the boxes that form a line is called a line box.

Quirks Mode and IE7 Mode (All Versions)

Right padding is ignored between inline formatted boxes.

IE8 Mode (All Versions)

Padding is lost after line breaks on inline level elements that contain block-level elements.


The specification states:

 When an inline box exceeds the width of a line box, it is split into several boxes 
 and these boxes are distributed across several line boxes. If an inline box cannot 
 be split (e.g., if the inline box contains a single character, or language specific 
 word breaking rules disallow a break within the inline box, or if the inline box is 
 affected by a white-space value of nowrap or pre), then the inline box overflows 
 the line box.

Quirks Mode (All Versions)

If an inline box cannot be split, then both the inline box and the line box overflow.


The specification states:

 A line box is always tall enough for all of the boxes it contains. However, it may 
 be taller than the tallest box it contains (if, for example, boxes are aligned so 
 that baselines line up). When the height of a box B is less than the height of the 
 line box containing it, the vertical alignment of B within the line box is 
determined by the 'vertical-align' property. When several inline level boxes 
cannot fit horizontally within a single line box, they are distributed among two 
or more vertically-stacked line boxes. Thus, a paragraph is a vertical stack of 
line boxes. Line boxes are stacked with no vertical separation and they never 

Quirks Mode and IE7 Mode (All Versions)

The following clarifications apply:

  • When the height of the inner box is less than the height of the line box containing it, the height of the inner box is clipped and is not preserved.

  • Characters are not placed in the center of the inner box when they are displayed, but are clipped from the bottom up.