CanvasRenderingContext2D.strokeStyle
The CanvasRenderingContext2D.strokeStyle
property of the Canvas 2D API specifies the color, gradient, or pattern to use for the strokes (outlines) around shapes. The default is #000
(black).
Note: For more examples of stroke and fill styles, see Applying styles and color in the Canvas tutorial.
Syntax
ctx.strokeStyle = color; ctx.strokeStyle = gradient; ctx.strokeStyle = pattern;
Options
color
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);
Result
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
Specification |
---|
HTML Standard (HTML) # dom-context-2d-strokestyle-dev |
Browser compatibility
Desktop | Mobile | |||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|
Chrome | Edge | Firefox | Internet Explorer | Opera | Safari | WebView Android | Chrome Android | Firefox for Android | Opera Android | Safari on IOS | Samsung Internet | |
strokeStyle |
1 |
12 |
1.5 |
9 |
≤12.1 |
2 |
1 |
18 |
4 |
≤12.1 |
1 |
1.0 |
WebKit/Blink-specific note
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
- The interface defining this property:
CanvasRenderingContext2D
CanvasGradient
CanvasPattern
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https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/strokeStyle