Web/API/CanvasRenderingContext2D/shadowColor

From Get docs


The CanvasRenderingContext2D.shadowColor property of the Canvas 2D API specifies the color of shadows.

Be aware that the shadow's rendered opacity will be affected by the opacity of the fillStyle color when filling, and of the strokeStyle color when stroking.

Note: Shadows are only drawn if the shadowColor property is set to a non-transparent value. One of the shadowBlur, shadowOffsetX, or shadowOffsetY properties must be non-zero, as well.


Syntax

ctx.shadowColor = color;
color
A DOMString parsed as a CSS <color> value. The default value is fully-transparent black.

Examples

Adding a shadow to shapes

This example adds a shadow to two squares; the first one is filled, and the second one is stroked. The shadowColor property sets the shadows' color, while shadowOffsetX and shadowOffsetY set their position relative to the shapes.

HTML

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

JavaScript

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

// Shadow
ctx.shadowColor = 'red';
ctx.shadowOffsetX = 10;
ctx.shadowOffsetY = 10;

// Filled rectangle
ctx.fillRect(20, 20, 100, 100);

// Stroked rectangle
ctx.lineWidth = 6;
ctx.strokeRect(170, 20, 100, 100);

Result

Shadows on translucent shapes

A shadow's opacity is affected by the transparency level of its parent object (even when shadowColor specifies a completely opaque value). This example strokes and fills a rectangle with translucent colors.

HTML

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

JavaScript

The resulting alpha value of the fill shadow is .8 * .2, or .16. The alpha of the stroke shadow is .8 * .6, or .48.

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

// Shadow
ctx.shadowColor = 'rgba(255, 0, 0, .8)';
ctx.shadowBlur = 8;
ctx.shadowOffsetX = 30;
ctx.shadowOffsetY = 20;

// Filled rectangle
ctx.fillStyle = 'rgba(0, 255, 0, .2)';
ctx.fillRect(10, 10, 150, 100);

// Stroked rectangle
ctx.lineWidth = 10;
ctx.strokeStyle = 'rgba(0, 0, 255, .6)';
ctx.strokeRect(10, 10, 150, 100);

Result

Specifications

Specification Status Comment
HTML Living StandardThe definition of 'CanvasRenderingContext2D.shadowColor' in that specification. Living Standard  

Browser compatibility

Update compatibility data on GitHub

Desktop Mobile
Chrome Edge Firefox Internet Explorer Opera Safari Android webview Chrome for Android Firefox for Android Opera for Android Safari on iOS Samsung Internet
shadowColor Chrome

Full support Yes

Edge

Full support 12

Firefox

Full support 1.5

IE

Full support Yes

Opera

Full support Yes

Safari

Full support Yes

WebView Android

Full support Yes

Chrome Android

Full support Yes

Firefox Android

Full support 4

Opera Android

Full support Yes

Safari iOS

Full support Yes

Samsung Internet Android

Full support Yes

Legend

Full support  
Full support


WebKit/Blink-specific notes

In WebKit- and Blink-based browsers, the non-standard and deprecated method ctx.setShadow() is implemented besides this property.

setShadow(width, height, blur, color, alpha);
setShadow(width, height, blur, graylevel, alpha);
setShadow(width, height, blur, r, g, b, a);
setShadow(width, height, blur, c, m, y, k, a);

See also