CanvasRenderingContext2D.measureText()

The CanvasRenderingContext2D.measureText() method returns a TextMetrics object that contains information about the measured text (such as its width, for example).

text

The text string to measure.

A TextMetrics object.

Given this <canvas> element:

<canvas id="canvas"></canvas>

... you can get a TextMetrics object using the following code:

const canvas = document.getElementById('canvas');
const ctx = canvas.getContext('2d');

let text = ctx.measureText('Hello world');
console.log(text.width);  // 56;

• The interface defining this method: CanvasRenderingContext2D
• TextMetrics