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The HTML <th>
element defines a cell as header of a group of table cells. The exact nature of this group is defined by the scope
and headers
attributes.
Content categories | None. |
---|---|
Permitted content |
Flow content, but with no header, footer, sectioning content, or heading content descendants.
|
Tag omission | The start tag is mandatory. The end tag may be omitted, if it is immediately followed by a <th> or <td> element or if there are no more data in its parent element. |
Permitted parents | A <tr> element. |
Permitted ARIA roles | Any |
DOM interface | HTMLTableHeaderCellElement |
Attributes
This element includes the global attributes.
abbr
in HTML5- This attribute contains a short abbreviated description of the cell's content. A user-agent (e.g., a speech reader) may be present in front of the description.
Usage Note: Do not use this attribute as it has become obsolete in the latest standard. Alternatively, you can put the abbreviated description inside the cell and place the long content in the title attribute.
align
in HTML 4, in HTML5- This enumerated attribute specifies how the cell content's horizontal alignment will be handled. Possible values are:
left
: The content is aligned to the left of the cell.center
: The content is centered in the cell.right
: The content is aligned to the right of the cell.justify
(with text only): The content is stretched out inside the cell so that it covers its entire width.char
(with text only): The content is aligned to a character inside the<th>
element with minimal offset. This character is defined by thechar
andcharoff
attributes.
The default value when this attribute is not specified is
left
.Usage Note: Do not use this attribute as it is obsolete in the latest standard.- To achieve the same effect as the
left
,center
,right
orjustify
values, apply the CSStext-align
property to the attribute. - To achieve the same effect as the
char
value, give thetext-align
property the same value you would use for thechar
. Unimplemented in CSS3.
axis
in HTML5- This attribute contains a list of space-separated strings. Each string is the
id
of a group of cells that this header applies to.Usage Note: Do not use this attribute as it is obsolete in the latest standard: use thescope
attribute instead. bgcolor
- This attribute defines the background color of each cell in a column. It consists of a 6-digit hexadecimal code as defined in sRGB and is prefixed by '#'. This attribute may be used with one of sixteen predefined color strings:
black
= "#000000"green
= "#008000"silver
= "#C0C0C0"lime
= "#00FF00"gray
= "#808080"olive
= "#808000"white
= "#FFFFFF"yellow
= "#FFFF00"maroon
= "#800000"navy
= "#000080"red
= "#FF0000"blue
= "#0000FF"purple
= "#800080"teal
= "#008080"fuchsia
= "#FF00FF"aqua
= "#00FFFF"Usage note: Do not use this attribute, as it is non-standard and only implemented in some versions of Microsoft Internet Explorer: The<th>
element should be styled using CSS. To create a similar effec use thebackground-color
property in CSS.
char
in HTML 4, in HTML5- The content of a column is aligned to a character in the
<th>
element. Typical values include a period (.) to align numbers or monetary values. Ifalign
is not set tochar
, this attribute is ignored.Usage Note: Do not use this attribute as it is no longer supported by the latest standard. To achieve the same effect , you can specify the character as the first value of thetext-align
property, Unimplemented in CSS3.
charoff
in HTML 4, in HTML5- This attribute is used to shift column data to the right of the character specified by the char attribute. Its value specifies the length of this shift.
Usage Note: Do not use this attribute as it is no longer supported by the latest standard.
colspan
- This attribute contains a positive integer value that indicates over how many columns a cell is extended. Its default value is
1.
If its value is set to0
, the cell is extended to the last element of the<colgroup>
. Values higher than 1000 are clipped down to 1000. headers
- This attribute contains a list of space-separated strings, each corresponding to the
id
attributes of other<th>
elements that relate to this element. rowspan
- This attribute contains a positive integer value that indicates over how many rows a cells is extended. Its default value is
1.
If its value is set to0
, the cell is extended to the last element of the table sections (<thead>
,<tbody>
or<tfoot>
). Values higher than 65534 are clipped down to 65534. scope
- This enumerated attribute defines the cells that the header (defined in the
<th>
) element relates to. It may have the following values:row
: The header relates to all cells of the row it belongs to.col
: The header relates to all cells of the column it belongs to.rowgroup
: The header belongs to a rowgroup and relates to all of its cells. These cells can be placed to the right or the left of the header, depending on the value of thedir
attribute in the<table>
element.colgroup
: The header belongs to a colgroup and relates to all of its cells.auto
valign
in HTML 4, in HTML5- This attribute specifies how a text is vertically aligned inside a cell. Possible values for this attribute are:
baseline
: Positions the text near the bottom of the cell and aligns it with the baseline of the characters instead of the bottom. If characters don't descend below the baseline, the baseline value achieves the same effect asbottom
.bottom
: Positions the text near the bottom of the cell.middle
: Centers the text in the cell.- and
top
: Positions the text near the top of the cell.
Usage Note: Do not use this attribute as it is no longer supported by the latest standard: use the CSSvertical-align
property instead. width
in HTML 4.01- This attribute is used to define a recommended cell width. Additional space can be added with the cellspacing and cellpadding properties and the width of the
<col>
element can also create extra width. But, if a column's width is too narrow to show a particular cell properly, it will be widened when displayed.Usage Note: Do not use this attribute in the latest standard: use the CSSwidth
property instead.
Examples
See <table>
for examples on <th>
.
Specifications
Specification | Status | Comment |
---|---|---|
WHATWG HTML Living Standard The definition of 'th element' in that specification. |
Living Standard | |
HTML5 The definition of 'th element' in that specification. |
Recommendation |
Browser compatibility
Feature | Chrome | Edge | Firefox (Gecko) | Internet Explorer | Opera | Safari |
---|---|---|---|---|---|---|
Basic support | 1.0 | (Yes) | 1.0 (1.7 or earlier) | (Yes) | (Yes) | (Yes) |
align/valign attribute |
1.0 | (Yes) | No support [1] | (Yes) | (Yes) | (Yes) |
char/charoff attribute |
1.0 | (Yes) | No support [2] | (Yes) | (Yes) | (Yes) |
bgcolor attribute |
No support | No support | No support | (Yes) | No support | No support |
Feature | Android | Edge | Firefox Mobile (Gecko) | IE Mobile | Opera Mobile | Safari Mobile |
---|---|---|---|---|---|---|
Basic support | (Yes) | (Yes) | 1.0 (1.0) | (Yes) | (Yes) | (Yes) |
align/valign attribute |
? | (Yes) | No support [1] | ? | ? | ? |
char/charoff attribute |
? | (Yes) | No support [2] | ? | ? | ? |
bgcolor attribute |
No support | No support | No support | (Yes) | No support | No support |
[1] See bug 915.
[2] See bug 2212.
See also
- Other table-related HTML Elements:
<caption>
,<col>
,<colgroup>
,<table>
,<tbody>
,<td>
,<tfoot>
,<thead>
,<tr>
.