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CanvasRenderingContext2D: shadowOffsetY 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.shadowOffsetY property of the Canvas 2D API specifies the distance that shadows will be offset vertically.

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.

Value

A float specifying the distance that shadows will be offset vertically. Positive values are down, and negative are up. The default value is 0 (no vertical offset). Infinity and NaN values are ignored.

Examples

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Moving a shadow vertically

This example adds a blurred shadow to a rectangle. The shadowColor property sets its color, shadowOffsetY sets its offset 25 units towards the bottom, and shadowBlur gives it a blur level of 10.

HTML

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

JavaScript

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

// Shadow
ctx.shadowColor = "red";
ctx.shadowOffsetY = 25;
ctx.shadowBlur = 10;

// Rectangle
ctx.fillStyle = "blue";
ctx.fillRect(20, 20, 150, 80);

Result

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

See also

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https://developer.mozilla.org/en-US/docs/Web/API/CanvasRenderingContext2D/shadowOffsetY