The alignment-baseline attribute specifies how an object is aligned with respect to its parent. This property specifies which baseline of this element is to be aligned with the corresponding baseline of the parent. For example, this allows alphabetic baselines in Roman text to stay aligned across font size changes. It defaults to the baseline with the same name as the computed value of the alignment-baseline property.
Note: As a presentation attribute alignment-baseline can be used as a CSS property.
You can use this attribute with the following SVG elements:
auto | baseline | before-edge | text-before-edge | middle | central | after-edge | text-after-edge | ideographic | alphabetic | hanging | mathematical | top | center | bottom
Default value
auto
Animatable
Yes
autoDeprecated
The value is the dominant-baseline of the script to which the character belongs - i.e., use the dominant-baseline of the parent.
baseline
Uses the dominant baseline choice of the parent. Matches the box's corresponding baseline to that of its parent.
before-edgeDeprecated
The alignment-point of the object being aligned is aligned with the "before-edge" baseline of the parent text content element.
text-bottom
Matches the bottom of the box to the top of the parent's content area.
text-before-edge
The alignment-point of the object being aligned is aligned with the "text-before-edge" baseline of the parent text content element.
Note: This keyword may be mapped to text-top.
middle
Aligns the vertical midpoint of the box with the baseline of the parent box plus half the x-height of the parent.
central
Matches the box's central baseline to the central baseline of its parent.
after-edgeDeprecated
The alignment-point of the object being aligned is aligned with the "after-edge" baseline of the parent text content element.
text-top
Matches the top of the box to the top of the parent's content area.
text-after-edge
The alignment-point of the object being aligned is aligned with the "text-after-edge" baseline of the parent text content element.
Note: This keyword may be mapped to text-bottom.
ideographic
Matches the box's ideographic character face under-side baseline to that of its parent.
alphabetic
Matches the box's alphabetic baseline to that of its parent.
hanging
The alignment-point of the object being aligned is aligned with the "hanging" baseline of the parent text content element.
mathematical
Matches the box's mathematical baseline to that of its parent.
top
Aligns the top of the aligned subtree with the top of the line box.
center
Aligns the center of the aligned subtree with the center of the line box.
bottom
Aligns the bottom of the aligned subtree with the bottom of the line box.
SVG 2 introduces some changes to the definition of this property. In particular: the values auto, before-edge, and after-edge have been removed. For backwards compatibility, text-before-edge may be mapped to text-top and text-after-edge to text-bottom. Neither text-before-edge nor text-after-edge should be used with the vertical-align property.