TextMetrics: alphabeticBaseline property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since October 2023.

Note: This feature is available in Web Workers.

The read-only alphabeticBaseline property of the TextMetrics interface is a double giving the distance from the horizontal line indicated by the CanvasRenderingContext2D.textBaseline property to the alphabetic baseline of the line box, in CSS pixels.

Examples

js
const canvas = document.createElement("canvas");
const ctx = canvas.getContext("2d");
const text = ctx.measureText("foo"); // returns TextMetrics object

text.alphabeticBaseline; // -0;

Specifications

Specification
HTML
# dom-textmetrics-alphabeticbaseline-dev

Browser compatibility

desktop mobile
Chrome
Edge
Firefox
Opera
Safari
Chrome Android
Firefox for Android
Opera Android
Safari on iOS
Samsung Internet
WebView Android
WebView on iOS
alphabeticBaseline
Chrome – Full support
Chrome 118 (Release date: 2023-10-10)
footnote Full support
Edge – Full support
Edge 118 (Release date: 2023-10-13)
footnote Full support
Firefox – Full support
Firefox 116 (Release date: 2023-08-01)
footnote Full support
Opera – Full support
Opera 104 (Release date: 2023-10-23)
footnote Full support
Safari – Full support
Safari 11.1 (Release date: 2018-04-12)
footnote Full support
Chrome Android – Full support
Chrome Android 118 (Release date: 2023-10-10)
footnote Full support
Firefox for Android – Full support
Firefox for Android 116 (Release date: 2023-08-01)
footnote Full support
Opera Android – Full support
Opera Android 79 (Release date: 2023-12-06)
footnote Full support
Safari on iOS – Full support
Safari on iOS 11.3 (Release date: 2018-03-29)
footnote Full support
Samsung Internet – Full support
Samsung Internet 25 (Release date: 2024-04-24)
footnote Full support
WebView Android – Full support
WebView Android 118 (Release date: 2023-10-10)
footnote Full support
WebView on iOS – Full support
WebView on iOS 11.3 (Release date: 2018-03-29)
footnote Full support

Legend

Tip: you can click/tap on a cell for more information.

Full support
Full support

See also