TextMetrics: fontBoundingBoxDescent property
Baseline
Widely available
This feature is well established and works across many devices and browser versions. It’s been available across browsers since August 2023.
Note: This feature is available in Web Workers.
The read-only fontBoundingBoxDescent property of the TextMetrics interface returns the distance from the horizontal line indicated by the CanvasRenderingContext2D.textBaseline attribute to the bottom of the bounding rectangle of all the fonts used to render the text, in CSS pixels.
Value
A number, in CSS pixels.
Examples
The code below shows how you can get the fontBoundingBoxDescent for text in a particular font.
js
const canvas = document.createElement("canvas");
const ctx = canvas.getContext("2d");
ctx.font = "25px serif";
const text = "Foo";
const textMetrics = ctx.measureText(text); // returns TextMetrics object
const descentCssPixels = textMetrics.fontBoundingBoxDescent;
The descent in CSS pixels for the text "Foo" in a 25px serif font is shown below.
Specifications
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| HTML # dom-textmetrics-fontboundingboxdescent-dev |
Browser compatibility
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fontBoundingBoxDescent
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