<th> - HTML: HyperText Markup Language 编辑

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.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

The source for this interactive example is stored in a GitHub repository. If you'd like to contribute to the interactive examples project, please clone https://github.com/mdn/interactive-examples and send us a pull request.

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.
Implicit ARIA role	columnheader or rowheader
Permitted ARIA roles	Any
DOM interface	HTMLTableCellElement

Attributes

This element includes the global attributes.

abbr

This attribute contains a short abbreviated description of the cell's content. Some user-agents, such as speech readers, may present this description before the content itself.

colspan

This attribute contains a non-negative integer value that indicates for how many columns the cell extends. Its default value is 1. Values higher than 1000 will be considered as incorrect and will be set to the default value (1).

headers

This attribute contains a list of space-separated strings, each corresponding to the id attribute of the <th> elements that apply to this element.

rowspan

This attribute contains a non-negative integer value that indicates for how many rows the cell extends. Its default value is 1; if its value is set to 0, it extends until the end of the table section (<thead>, <tbody>, <tfoot>, even if implicitly defined), that the cell belongs to. 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 the dir attribute in the <table> element.
• colgroup: The header belongs to a colgroup and relates to all of its cells.
• auto

The default value when this attribute is not specified is auto.

Deprecated attributes

align Obsolete since 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 the char and charoff attributes.

The default value when this attribute is not specified is left.

Note: Do not use this attribute as it is obsolete in the latest standard.

• To achieve the same effect as the left, center, right or justify values, apply the CSS text-align property to the element.
• To achieve the same effect as the char value, give the text-align property the same value you would use for the char. Unimplemented in CSS3.

axis Obsolete since 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. Note: Do not use this attribute as it is obsolete in the latest standard: use the scope 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"

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 effect use the background-color property in CSS instead.

char Obsolete since HTML5

The content in the cell element is aligned to a character. Typical values include a period (.) to align numbers or monetary values. If align is not set to char, this attribute is ignored. Note: Do not use this attribute as it is obsolete in the latest standard. To achieve the same effect, you can specify the character as the first value of the text-align property, Unimplemented in CSS3.

charoff Obsolete since 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. Note: Do not use this attribute as it is obsolete in the latest standard.

height Deprecated since HTML4, Obsolete since HTML5

This attribute is used to define a recommended cell height. Note: Do not use this attribute as it is obsolete in the latest standard: use the CSS height property instead.

valign Obsolete since 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 as bottom.
• 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.

Note: Do not use this attribute as it is obsolete in the latest standard: use the CSS vertical-align property instead.

width Deprecated since HTML4, Obsolete since HTML5

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. Note: Do not use this attribute as it is obsolete in the latest standard: use the CSS width property instead.

Examples

See <table> for examples on <th>.

Specifications

Specification	Status	Comment
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

BCD tables only load in the browser

See also

• Other table-related HTML Elements: <caption>, <col>, <colgroup>, <table>, <tbody>, <td>, <tfoot>, <thead>, <tr>.