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The <time> CSS data type represents a time value expressed in seconds or milliseconds.


A time consists of a​ ​​​​​​<number> followed by a unit. As with all dimensions, there is no space between the unit literal and the number.

Although the number 0 is always the same regardless of unit, the unit may not be omitted. In other words, 0 is invalid and does not represent 0s or 0ms.


Represents a time in seconds. Examples: 0s, 1.5s, -60s.
Represents a time in milliseconds. Examples: 0ms, 1500ms, -60000ms.

Conversion between s and ms follows the logical 1s = 1000ms.


Valid time values

12s         Positive integer
-456ms      Negative integer
4.3ms       Non-integer
14mS        The unit is case-insensitive, although capital letters are not recommended.
+0s         Zero with a leading + and a unit
-0ms        Zero with a leading - and a unit

Invalid time values

0           Although unitless zero is allowed for <length>s, it's invalid for <time>s.
12.0        This is a <number>, not a <time>, because it's missing a unit.
7 ms        No space is allowed between the number and the unit.


Specification Status Comment
CSS Values and Units Module Level 3
The definition of '<time>' in that specification.
Candidate Recommendation Normative definition of s and ms.
CSS Level 2 (Revision 1)
The definition of '<time>' in that specification.
Recommendation Informal definition of s and ms.

Browser compatibility

Feature Chrome Firefox (Gecko) Internet Explorer Opera Safari
Basic support (Yes) 4.0 (2.0) 9.0 10.5 (2.3) (Yes)
Feature Android Firefox Mobile (Gecko) IE Mobile Opera Mobile Safari Mobile
Basic support ? ? ? No support ?

Document Tags and Contributors

 Last updated by: mfluehr,