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CanvasRenderingContext2D.createRadialGradient

The CanvasRenderingContext2D.createRadialGradient() method of the Canvas 2D API creates a radial gradient using the size and coordinates of two circles.

This method returns a CanvasGradient. To be applied to a shape, the gradient must first be assigned to the fillStyle or strokeStyle properties.

Note: Gradient coordinates are global, i.e., relative to the current coordinate space. When applied to a shape, the coordinates are NOT relative to the shape's coordinates.

Syntax

CanvasGradient ctx.createRadialGradient(x0, y0, r0, x1, y1, r1);

The createRadialGradient() method is specified by six parameters, three defining the gradient's start circle, and three defining the end circle.

Parameters

x0: The x-axis coordinate of the start circle.
y0: The y-axis coordinate of the start circle.
r0: The radius of the start circle. Must be non-negative and finite.
x1: The x-axis coordinate of the end circle.
y1: The y-axis coordinate of the end circle.
r1: The radius of the end circle. Must be non-negative and finite.

Return value

CanvasGradient: A radial CanvasGradient initialized with the two specified circles.

Examples

Filling a rectangle with a radial gradient

This example initializes a radial gradient using the createRadialGradient() method. Three color stops between the gradient's two circles are then created. Finally, the gradient is assigned to the canvas context, and is rendered to a filled rectangle.

HTML

<canvas id="canvas" width="200" height="200"></canvas>

JavaScript

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

// Create a radial gradient
// The inner circle is at x=110, y=90, with radius=30
// The outer circle is at x=100, y=100, with radius=70
var gradient = ctx.createRadialGradient(110,90,30, 100,100,70);

// Add three color stops
gradient.addColorStop(0, 'pink');
gradient.addColorStop(.9, 'white');
gradient.addColorStop(1, 'green');

// Set the fill style and draw a rectangle
ctx.fillStyle = gradient;
ctx.fillRect(20, 20, 160, 160);

Result

Specifications

Specification	Status	Comment
HTML Living Standard The definition of 'CanvasRenderingContext2D.createRadialGradient' in that specification.	Living Standard

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

Gecko-specific notes

Starting with Gecko 2.0 (Firefox 4 / Thunderbird 3.3 / SeaMonkey 2.1), specifying non-finite values now throws NOT_SUPPORTED_ERR instead of SYNTAX_ERR.
Starting with Gecko 5.0 (Firefox 5.0 / Thunderbird 5.0 / SeaMonkey 2.2), specifying a negative radius correctly throws INDEX_SIZE_ERR.