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CanvasRenderingContext2D.strokeStyle

The CanvasRenderingContext2D.strokeStyle property of the Canvas 2D API specifies the color, gradient, or pattern to use for the strokes (border lines) around shapes. The default is #000 (black).

For more examples of stroke and fill styles, see the chapter Applying styles and color in the Canvas tutorial.

Syntax

ctx.strokeStyle = color;
ctx.strokeStyle = gradient;
ctx.strokeStyle = pattern;

Options

color
A DOMString parsed as CSS <color> value.
gradient
A CanvasGradient object (a linear or radial gradient).
pattern
A CanvasPattern object (a repeating image).

Examples

Changing the stroke color of a shape

This example applies a blue stroke color to a rectangle.

HTML

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

JavaScript

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

ctx.strokeStyle = 'blue';
ctx.strokeRect(10, 10, 100, 100);

Creating multiple stroke colors using loops

In this example, we use two for loops and the arc() method to draw a grid of circles, each having a different stroke color. To achieve this, we use the two variables i and j to generate a unique RGB color for each circle, and only modify the green and blue values. (The red channel has a fixed value.)

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

for (let i = 0; i < 6; i++) {
  for (let j = 0; j < 6; j++) {
    ctx.strokeStyle = `rgb(
        0,
        ${Math.floor(255 - 42.5 * i)},
        ${Math.floor(255 - 42.5 * j)})`;
    ctx.beginPath();
    ctx.arc(12.5 + j * 25, 12.5 + i * 25, 10, 0, Math.PI * 2, true);
    ctx.stroke();
  }
}

The result looks like this:

Screenshot Live sample

Specifications

Browser compatibilityUpdate compatibility data on GitHub

Desktop
Chrome Edge Firefox Internet Explorer Opera Safari
Basic support Yes 12 Yes Yes Yes Yes
Mobile
Android webview Chrome for Android Edge Mobile Firefox for Android Opera for Android iOS Safari Samsung Internet
Basic support Yes Yes Yes Yes Yes Yes Yes

In WebKit- and Blink-based browsers, the non-standard and deprecated method ctx.setStrokeColor() is implemented in addition to this property.

setStrokeColor(color, optional alpha);
setStrokeColor(grayLevel, optional alpha);
setStrokeColor(r, g, b, a);
setStrokeColor(c, m, y, k, a);

See also

© 2005–2018 Mozilla Developer Network and individual contributors.
Licensed under the Creative Commons Attribution-ShareAlike License v2.5 or later.
https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/strokeStyle