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The CanvasRenderingContext2D.rect() method of the Canvas 2D API creates a path for a rectangle at position (x, y) with a size that is determined by width and height. Those four points are connected by straight lines and the sub-path is marked as closed, so that you can fill or stroke this rectangle.

Syntax

void ctx.rect(x, y, width, height);

Parameters

x
The x coordinate for the left side of the rectangle.
y
The y coordinate for the top of the rectangle.
width
The rectangle's width.
height
The rectangle's height.

Examples

Using the rect method

This is just a simple code snippet which uses the rect method to create a path. To actually draw that path onto the canvas, you can use the fill() or stroke() method. See also the fillRect() and strokeRect() methods, which can do this in one step.

HTML

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

JavaScript

var canvas = document.getElementById('canvas');
var ctx = canvas.getContext('2d');
ctx.rect(10, 10, 100, 100);
ctx.fill();

Edit the code below and see your changes update live in the canvas:

Playable code
<canvas id="canvas" width="400" height="200" class="playable-canvas"></canvas>
<div class="playable-buttons">
  <input id="edit" type="button" value="Edit" />
  <input id="reset" type="button" value="Reset" />
</div>
<textarea id="code" class="playable-code">
ctx.rect(10, 10, 100, 100);
ctx.fill();</textarea>
var canvas = document.getElementById("canvas");
var ctx = canvas.getContext("2d");
var textarea = document.getElementById("code");
var reset = document.getElementById("reset");
var edit = document.getElementById("edit");
var code = textarea.value;

function drawCanvas() {
  ctx.clearRect(0, 0, canvas.width, canvas.height);
  eval(textarea.value);
}

reset.addEventListener("click", function() {
  textarea.value = code;
  drawCanvas();
});

edit.addEventListener("click", function() {
  textarea.focus();
})

textarea.addEventListener("input", drawCanvas);
window.addEventListener("load", drawCanvas);

Specifications

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

Browser compatibility

FeatureChromeEdgeFirefoxInternet ExplorerOperaSafari
Basic support Yes12 Yes Yes Yes Yes
FeatureAndroid webviewChrome for AndroidEdge mobileFirefox for AndroidOpera AndroidiOS SafariSamsung Internet
Basic support Yes Yes Yes Yes Yes Yes Yes

See also

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