This feature is well established and works across many devices and browser versions. It’s been available across browsers since July 2015.
The unitType property of the SVGLength interface that represents type of the value as specified by one of the SVG_LENGTHTYPE_* constants defined on this interface.
One of the following:
SVGLength.SVG_LENGTHTYPE_UNKNOWN (0)SVGLength.SVG_LENGTHTYPE_NUMBER (1)SVGLength.SVG_LENGTHTYPE_PERCENTAGE (2)SVGLength.SVG_LENGTHTYPE_EMS (3)SVGLength.SVG_LENGTHTYPE_EXS (4)SVGLength.SVG_LENGTHTYPE_PX (5)SVGLength.SVG_LENGTHTYPE_CM (6)SVGLength.SVG_LENGTHTYPE_MM (7)SVGLength.SVG_LENGTHTYPE_IN (8)SVGLength.SVG_LENGTHTYPE_PT (9)SVGLength.SVG_LENGTHTYPE_PC (10)Here's an example of how to access the unitType property:
// Get an SVGLength object
const svg = document.querySelector("svg");
// Assume `length` is an instance of SVGLength
const length = svg.createSVGLength();
// Set the length value
length.newValueSpecifiedUnits(SVGLength.SVG_LENGTHTYPE_PERCENTAGE, 20);
// Check the unit type
console.log(length.unitType); // Output: 2 (SVG_LENGTHTYPE_PERCENTAGE)
| Desktop | Mobile | |||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Chrome | Edge | Firefox | Opera | Safari | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | WebView Android | WebView on iOS | |
unitType |
1 | 12 | 1.5 | ≤12.1 | 3 | 18 | 4 | ≤12.1 | 1 | 1.0 | 4.4 | 1 |
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https://developer.mozilla.org/en-US/docs/Web/API/SVGLength/unitType