<frequency-percentage>
The <frequency-percentage> CSS data type represents a value that can be either a <frequency> or a <percentage>. Frequency values, e.g., the pitch of a speaking voice, are not currently used in any CSS properties.
Syntax
The value of a <frequency-percentage> is either a <frequency> or a <percentage>; see their individual reference pages for details about their syntaxes.
Description
Use in calc()
Where a <frequency-percentage> is specified as an allowable type, this means that the percentage resolves to a frequency and therefore can be used in a calc() expression.
Formal syntax
<frequency-percentage> =
<frequency> |
<percentage>
Examples
Valid percentage values
90% Positive percentage +90% Positive percentage with leading + -90% Negative percentage — not valid for all properties that use percentages
Invalid percentage values
90 % No space is allowed between the number and the unit
Valid frequency values
12Hz Positive integer 4.3Hz Non-integer 14KhZ The unit is case-insensitive, though non-SI capitalization is not recommended. +0Hz Zero, with a leading + and a unit -0kHz Zero, with a leading - and a unit
Invalid frequency values
12.0 This is a <number>, not an <frequency>, because it is missing a unit. 7 Hz No space is allowed between the number and the unit. 0 Although unitless zero is an allowable <length>, it's an invalid <frequency>.
Specifications
| Specification |
|---|
| CSS Values and Units Module Level 4 # typedef-frequency-percentage |
Browser compatibility
Currently, no browsers support this feature.
See also
- CSS data types
- CSS values and units module
- Related CSS data types: