JavaScript: Draw a circle

Last update on March 06 2025 07:19:51 (UTC/GMT +8 hours)

JavaScript Drawing: Exercise-2 with Solution

Draw Circle

Write a JavaScript program to draw a circle.

Sample output:

Sample Solution:

HTML Code:

<!DOCTYPE html>
  <html>
  <head>
  <meta charset=utf-8 />
  <title>Draw a circle</title>
  </head>
  <body onload="draw();">
  <canvas id="circle" width="150" height="150"></canvas>
  </body>
  </html>

JavaScript Code:

function draw()
  {
var canvas = document.getElementById('circle');
if (canvas.getContext)
{
var ctx = canvas.getContext('2d'); 
var X = canvas.width / 2;
var Y = canvas.height / 2;
var R = 45;
ctx.beginPath();
ctx.arc(X, Y, R, 0, 2 * Math.PI, false);
ctx.lineWidth = 3;
ctx.strokeStyle = '#FF0000';
ctx.stroke();
}
}

Live Demo:

See the Pen javascript-drawing-exercise-2 by w3resource (@w3resource) on CodePen.

For more Practice: Solve these Related Problems:

Write a JavaScript program to draw a circle with a radial gradient that transitions from a bright center to a dark edge.
Write a JavaScript program to draw a circle with only an outline (no fill) and a thick stroke.
Write a JavaScript program to draw a circle with a drop shadow effect to give it a 3D appearance.
Write a JavaScript program to draw an array of circles arranged in a grid pattern with varying colors.

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