Definition and Usage

The datetime attribute specifies a standardized, machine-readable date or time for the element.

This attribute is used with tags such as <del>, <ins>, and <time>.
By providing a standardized, machine‑readable date or time, it helps content authors, screen readers, and search engines better understand and process the information.

Basic Example

HTML 
<p>
    The concert was held <time datetime="2001-05-15 19:00">yesterday</time>.
</p>
Rendered Output

Applicable Elements and Uses of the datetime Attribute

Applicable Elements and Uses of the datetime Attribute
<del> Specifies the date or time when the content was deleted.
<ins> Specifies the date or time when the content was inserted.
<time> Specifies a standardized, machine-readable date or time..

The datetime attribute is not required; it is optional and can be used as needed.

When users view a web page, the value of the datetime attribute is not displayed. However, by using the datetime attribute to specify a standardized, machine-readable date or time related to the content, content authors, screen readers, and search engines can better understand and process the information.

This standardized, machine-readable date or time refers to a valid value of the datetime attribute and must conform to one of the appropriate formats listed in the table below.

Valid datetime Values
Valid datetime Value FormatExample
Valid year string 2011
(Represents the year only)
Valid year-month string 2011-11
(Represents the year and month)
Valid year-month-day string 2011-11-18
(Represents the year, month, and day)
Valid month-day string 11-18
(Represents the month and day)
Valid week string 2011-W47
(Indicates the 47th week of 2011)
Valid time string 14:54
(Represents the hour and minute)
14:54:39
(Represents hour, minute, and second)
14:54:39.929
(Represents hour, minute, second, and millisecond)
Valid time-zone offset string Z
(UTC (Coordinated Universal Time, zero offset) – equivalent to +00:00)
+0000
(UTC with no offset)
+00:00
(UTC with no offset, colon added for readability)
-0800
(8 hours behind UTC – e.g., Pacific Standard Time (PST))
-08:00
(Same as above, but colon included for readability)
Valid local date and time string 2011-11-18T14:54:39.929
(Date and time separated by a 'T')
2011-11-18 14:54:39.929
(Date and time separated by a space)
Valid international date and time string
(Indicates UTC timezone)		 2011-11-18T14:54:39.929Z
2011-11-18T14:54:39.929-0400
2011-11-18T14:54:39.929-04:00
2011-11-18 14:54:39.929Z
2011-11-18 14:54:39.929-0400
2011-11-18 14:54:39.929-04:00
Valid duration string PT4H18M3S
(Represents a duration of hours, minutes, and seconds)

Examples

Check out how the datetime attribute is used with the <del>, <ins>, and <time> tags through the following examples.

Using the cite attribute with <del>

HTML 
<p>
    The following feature has been removed.
    <del cite="https://example.com/changelog" datetime="2022-11-14">
        Details about the removed feature...
    </del>
</p>

In this example, the datetime attribute specifies the date or time when the content was deleted within the <del> tag.

Using the cite attribute with <ins>

HTML 
<p>
    This is a description of the latest update.
    <ins cite="https://example.com/changelog" datetime="2022-11-14">
        Details about the latest update...
    </ins>
</p>

In this example, the datetime attribute specifies the date or time when the content was inserted within the <ins> tag.

Using the cite attribute with <time>

HTML 
<p>
    The next meeting is scheduled for <time datetime="2023-09-11T14:30:00">2:30 PM tomorrow</time>.
</p>

In this example, the datetime attribute specifies an explicit date and time within the <time> tag.

Specifications

Specification for the datetime Attribute
Specification
<ins>,<del> datetime HTML Standard
#attributes-common-to-ins-and-del-elements
<time> datetime HTML Standard
#attr-time-datetime

Browser compatibility

The datetime attribute has the following browser compatibility across supported tags.

Browser compatibility for the datetime Attribute
Attribute
Desktop Chrome
Chrome
DesktopDesktop Edge
Edge
Desktop Firefox
Firefox
Safari
Safari
<del> datetime 1 12 1 4
<ins> datetime 1 12 1 4
<time> datetime 62 18 22 7

References

See also