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CanvasRenderingContext2D: lineWidth property

Baseline Widely available

This feature is well established and works across many devices and browser versions. It’s been available across browsers since ⁨July 2015⁩.

The CanvasRenderingContext2D.lineWidth property of the Canvas 2D API sets the thickness of lines.

Note: Lines can be drawn with the stroke(), strokeRect(), and strokeText() methods.

Value

A number specifying the line width, in coordinate space units. Zero, negative, Infinity, and NaN values are ignored. This value is 1.0 by default.

Examples

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Changing line width

This example draws a line and a rectangle, using a line width of 15 units.

HTML

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

JavaScript

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

ctx.lineWidth = 15;

ctx.beginPath();
ctx.moveTo(20, 20);
ctx.lineTo(130, 130);
ctx.rect(40, 40, 70, 70);
ctx.stroke();

Result

More examples

For more examples and explanation about this property, see Applying styles and color in the Canvas Tutorial.

Specifications

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
lineWidth 1 12 1.5 ≤12.1 2 18 4 ≤12.1 1 1.0 4.4 1

See also

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Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/lineWidth